NEXTLINK COMMUNICATIONS, INC.

                                       TO

                     UNITED STATES TRUST COMPANY OF NEW YORK
                                                     TRUSTEE


                             ----------------------


                                   Indenture

                         Dated as of September 25, 1997


                             ----------------------




                                  $400,000,000


                                9 5/8% SENIOR NOTES
                                    DUE 2007







                          NEXTLINK COMMUNICATIONS, INC.

                 Certain Sections of this Indenture relating to
                         Sections 310 through 318 of the
                          Trust Indenture Act of 1939:



Trust Indenture                                             Indenture
  Act Section                                                Section 
  -----------                                                ------- 
                                                        
Section 310(a)(1) ......................................      609
           (a)(2) ......................................      609
           (a)(3) ...................................... Not Applicable
           (a)(4) ...................................... Not Applicable
           (b) .........................................      608
                                                              610
Section 311(a) .........................................      613
           (b) .........................................      613
Section 312(a) .........................................      701
           (b) .........................................      702
           (c) .........................................      702
Section 313(a) .........................................      703
           (b) .........................................      703
           (c) .........................................      703
           (d) .........................................      703
Section 314(a) .........................................      704
                                                              1018
           (b) ......................................... Not Applicable
           (c)(1) ......................................      102
           (c)(2) ......................................      102
           (c)(3) ...................................... Not Applicable
           (d) ......................................... Not Applicable
           (e) .........................................      102
Section 315(a) .........................................      601
           (b) .........................................      602
           (c) .........................................      601
           (d) .........................................      601
           (e) .........................................      514
Section 316(a)(1)(A) ...................................      502
                                                              512
           (a)(1)(B) ...................................      513


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Note:    This table of contents shall not, for any purpose, be deemed
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Trust Indenture                                             Indenture
  Act Section                                                Section 
  -----------                                                ------- 
                                                        
           (a)(2) ...................................... Not Applicable
           (b) .........................................      508
           (c) .........................................      104
Section 317(a)(1) ......................................      503
           (a)(2) ......................................      504
           (b) .........................................      1003
Section 318(a) .........................................      107


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Note:    This table of contents shall not, for any purpose, be deemed
         to be a part of the Indenture.


                                      -ii-



                                TABLE OF CONTENTS



                                                                                                               PAGE
                                                                                                               ----
                                                                                                           
Parties...................................................................................................       1
Recitals of the Company...................................................................................       1


                                   ARTICLE ONE

                       Definitions and Other Provisions of
                               General Application


SECTION 101.         Definitions:
                                                                                                        
                     Act..................................................................................       2
                     Acquired Debt........................................................................       2
                     Affiliate............................................................................       2
                     Agent Member.........................................................................       2
                     Asset Disposition....................................................................       2
                     Attributable Value...................................................................       3
                     Bank Credit Agreement ...............................................................       4
                     Board of Directors...................................................................       4
                     Board Resolution.....................................................................       4
                     Business Day.........................................................................       4
                     Capital Lease Obligation.............................................................       4
                     Capital Stock........................................................................       4
                     Change of Control ...................................................................       4
                     Commission...........................................................................       4
                     Common Equity........................................................................       5
                     Company..............................................................................       5
                     Company Request; Company Order.......................................................       5
                     Consolidated Capital Ratio...........................................................       5
                     Consolidated Cash Flow Available for
                       Fixed Charges......................................................................       5
                     Consolidated Income Tax Expense......................................................       6
                     Consolidated Interest Expense........................................................       6
                     Consolidated Net Income..............................................................       6
                     Consolidated Net Worth...............................................................       7
                     Consolidated Tangible Assets.........................................................       7
                     Corporate Trust Office...............................................................       7
                     corporation..........................................................................       7
                     Debt.................................................................................       8
                     Default..............................................................................       8
                     Defaulted Interest...................................................................       8
                     Depository...........................................................................       9


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                                                                                                               PAGE
                                                                                                               ----
                                                                                                         
                     Disqualified Stock...................................................................       9
                     DTC..................................................................................       9
                     Eagle River..........................................................................       9
                     Eligible Institution.................................................................       9
                     Event of Default.....................................................................      10
                     Exchange Act.........................................................................      10
                     Expiration Date......................................................................      10
                     Global Security......................................................................      10
                     Government Securities................................................................      10
                     Guarantee............................................................................      10
                     Holder...............................................................................      10
                     Incur................................................................................      11
                     Indenture............................................................................      11
                     Interest Payment Date................................................................      11
                     Interest Rate or Currency Protection
                       Agreement..........................................................................      11
                     Investment...........................................................................      11
                     Issue Date...........................................................................      12
                     Joint Venture........................................................................      12
                     Lien.................................................................................      12
                     Marketable Securities................................................................      12
                     Maturity.............................................................................      13
                     Net Available Proceeds...............................................................      13
                     Offer to Purchase....................................................................      14
                     Officers' Certificate................................................................      16
                     Opinion of Counsel...................................................................      17
                     Outstanding..........................................................................      17
                     Paying Agent.........................................................................      18
                     Permitted Interest Rate or Currency
                       Protection Agreement...............................................................      18
                     Permitted Investment.................................................................      18
                     Permitted Liens......................................................................      18
                     Person...............................................................................      19
                     Predecessor Security.................................................................      19
                     Preferred Dividends..................................................................      20
                     Preferred Stock......................................................................      20
                     Purchase Date........................................................................      20
                     Purchase Money Debt..................................................................      20
                     readily marketable cash equivalents..................................................      20
                     Receivables..........................................................................      21
                     Receivables Sale.....................................................................      21
                     Redemption Date......................................................................      21
                     Redemption Price.....................................................................      21


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                                                                                                               PAGE
                                                                                                               ----
                                                                                                        
                     Regular Record Date..................................................................      21
                     Related Person.......................................................................      21
                     Responsible Officer..................................................................      21
                     Restricted Subsidiary................................................................      22
                     Sale and Leaseback Transaction.......................................................      22
                     SEC Reports..........................................................................      22
                     Securities...........................................................................      22
                     Securities Act.......................................................................      22
                     Security Register; Security Registrar................................................      22
                     Significant Subsidiary...............................................................      22
                     Special Record Date..................................................................      22
                     Stated Maturity......................................................................      23
                     Subordinated Debt....................................................................      23
                     Subsidiary...........................................................................      24
                     Successor Security...................................................................      24
                     Telecommunications Assets............................................................      24
                     Telecommunications Business..........................................................      24
                     Trustee..............................................................................      25
                     Trust Indenture Act..................................................................      25
                     Unrestricted Subsidiary..............................................................      25
                     Vendor Financing Facility............................................................      26
                     Vice President.......................................................................      26
                     Voting Stock.........................................................................      26
                     Wholly-Owned Restricted Subsidiary...................................................      26

SECTION 102.         Compliance Certificates and
                       Opinions...........................................................................      26

SECTION 103.         Form of Documents Delivered to
                       Trustee............................................................................      27

SECTION 104.         Acts of Holders; Record Dates........................................................      28

SECTION 105.         Notices, Etc., to Trustee and
                       Company............................................................................      31

SECTION 106.         Notice to Holders; Waiver............................................................      31

SECTION 107.         Conflict with Trust Indenture Act....................................................      32

SECTION 108.         Effect of Headings and
                       Table of Contents..................................................................      32


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                                      -v-






                                                                                                               PAGE
                                                                                                               ----
                                                                                                        
SECTION 109.         Successors and Assigns...............................................................      32

SECTION 110.         Separability Clause..................................................................      32

SECTION 111.         Benefits of Indenture................................................................      32

SECTION 112.         Governing Law........................................................................      33

SECTION 113.         Legal Holidays.......................................................................      33


                                   ARTICLE TWO

                                 Security Forms

SECTION 201.         Forms Generally......................................................................      33

SECTION 202.         Form of Face of Security.............................................................      34

SECTION 203.         Form of Reverse of Security..........................................................      36

SECTION 204.         Additional Provisions Required
                       in Global Security.................................................................      41

SECTION 205.         Form of Trustee's Certificate of
                       Authentication.....................................................................      41


                                 ARTICLE THREE

                                The Securities

SECTION 301.         Title and Terms......................................................................      42

SECTION 302.         Denominations........................................................................      43

SECTION 303.         Execution, Authentication,
                       Delivery and Dating................................................................      43

SECTION 304.         Temporary Securities.................................................................      44

SECTION 305.         Registration, Registration of
                        Transfer and Exchange.............................................................      44


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                                                                                                               PAGE
                                                                                                               ----
                                                                                                        
SECTION 306.         Mutilated, Destroyed, Lost and
                       Stolen Securities..................................................................      47

SECTION 307.         Payment of Interest; Interest Rights
                       Preserved..........................................................................      48

SECTION 308.         Persons Deemed Owners................................................................      49

SECTION 309.         Cancellation.........................................................................      50

SECTION 310.         Computation of Interest..............................................................      50

SECTION 311.         CUSIP Numbers........................................................................      50
 

                                 ARTICLE FOUR

                           Satisfaction and Discharge

SECTION 401.         Satisfaction and Discharge of
                       Indenture..........................................................................      50

SECTION 402.         Application of Trust Money...........................................................      52


                                ARTICLE FIVE

                                  Remedies

SECTION 501.         Events of Default....................................................................      52

SECTION 502.         Acceleration of Maturity; Rescission
                       and Annulment......................................................................      55

SECTION 503.         Collection of Indebtedness and Suits
                       for Enforcement by Trustee.........................................................      56

SECTION 504.         Trustee May File Proofs of Claim.....................................................      57

SECTION 505.         Trustee May Enforce Claims Without
                       Possession of Securities...........................................................      58

SECTION 506.         Application of Money Collected.......................................................      58


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                                     -vii-






                                                                                                               PAGE
                                                                                                               ----
                                                                                                        
SECTION 507.         Limitation on Suits..................................................................      58

SECTION 508.         Unconditional Right of Holders to
                       Receive Principal, Premium and
                       Interest ..........................................................................      59

SECTION 509.         Restoration of Rights and Remedies...................................................      60

SECTION 510.         Rights and Remedies Cumulative.......................................................      60

SECTION 511.         Delay or Omission Not Waiver.........................................................      60

SECTION 512.         Control by Holders...................................................................      61

SECTION 513.         Waiver of Past Defaults..............................................................      61

SECTION 514.         Undertaking for Costs................................................................      62

SECTION 515.         Waiver of Stay or Extension Laws.....................................................      62


                                   ARTICLE SIX

                                   The Trustee

SECTION 601.         Certain Duties and Responsibilities..................................................      62

SECTION 602.         Notice of Defaults...................................................................      63

SECTION 603.         Certain Rights of Trustee............................................................      63

SECTION 604.         Not Responsible for Recitals or
                       Issuance of Securities.............................................................      64

SECTION 605.         May Hold Securities..................................................................      65

SECTION 606.         Money Held in Trust..................................................................      65

SECTION 607.         Compensation and Reimbursement.......................................................      65

SECTION 608.         Disqualification; Conflicting
                       Interests..........................................................................      66


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                                     -viii-






                                                                                                               PAGE
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SECTION 609.         Corporate Trustee Required;
                       Eligibility........................................................................      66

SECTION 610.         Resignation and Removal; Appointment
                       of Successor.......................................................................      67

SECTION 611.         Acceptance of Appointment by
                       Successor..........................................................................      68

SECTION 612.         Merger, Conversion, Consolidation
                       or Succession to Business..........................................................      69

SECTION 613.         Preferential Collection of Claims
                       Against Company....................................................................      69

SECTION 614.         Appointment of Authenticating Agent..................................................      69


                                  ARTICLE SEVEN

              Holders' Lists and Reports by Trustee and The Company

SECTION 701.         Company to Furnish Trustee Names
                       and Addresses of Holders...........................................................      71

SECTION 702.         Preservation of Information;
                       Communications to Holders..........................................................      72

SECTION 703.         Reports by Trustee...................................................................      72

SECTION 704.         Reports by Company ..................................................................      73


                                  ARTICLE EIGHT

                           Merger, Consolidation, Etc.

SECTION 801.         Mergers, Consolidations and Certain
                       Sales of Assets....................................................................      73

SECTION 802.         Successor Substituted................................................................      75


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                                      -ix-






                                                                                                               PAGE
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                                  ARTICLE NINE

                             Supplemental Indentures

SECTION 901.         Supplemental Indentures Without
                       Consent of Holders.................................................................      75

SECTION 902.         Supplemental Indentures with
                       Consent of Holders.................................................................      76

SECTION 903.         Execution of Supplemental Indentures.................................................      77

SECTION 904.         Effect of Supplemental Indentures....................................................      77

SECTION 905.         Conformity with Trust Indenture Act..................................................      78

SECTION 906.         Reference in Securities to
                       Supplemental Indentures............................................................      78


                                   ARTICLE TEN
 
                                    Covenants

SECTION 1001.        Payment of Principal, Premium and
                       Interest...........................................................................      78

SECTION 1002.        Maintenance of Office or Agency......................................................      78

SECTION 1003.        Money for Security Payments to be
                       Held in Trust......................................................................      79

SECTION 1004.        Existence............................................................................      81

SECTION 1005.        Maintenance of Properties and
                       Insurance..........................................................................      81

SECTION 1006.        Payment of Taxes and Other Claims....................................................      82

SECTION 1007.        Limitation on Consolidated Debt......................................................      82

SECTION 1008.        Limitation on Debt and Preferred
                       Stock of Restricted Subsidiaries...................................................      85


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                                                                                                               PAGE
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SECTION 1009.        Limitation on Restricted Payments....................................................      88

SECTION 1010.        Limitations on Dividend and Other
                       Payment Restrictions Affecting
                       Restricted Subsidiaries............................................................      90

SECTION 1011.        Limitation on Liens  ................................................................      91

SECTION 1012.        Limitation on Sale and Leaseback
                       Transactions.......................................................................      93

SECTION 1013.        Limitation on Asset Dispositions.....................................................      93

SECTION 1014.        Limitation on Issuances and Sales
                       of Capital Stock of Restricted
                       Subsidiaries.......................................................................      95

SECTION 1015.        Transactions with Affiliates and
                       Related Persons....................................................................      96

SECTION 1016.        Change of Control....................................................................      97

SECTION 1017.        Provision of Financial Information...................................................      98

SECTION 1018.        Statement by Officers as to Default..................................................      98

SECTION 1019.        Waiver of Certain Covenants..........................................................      99


                                 ARTICLE ELEVEN

                            Redemption of Securities

SECTION 1101.        Right of Redemption..................................................................      99

SECTION 1102.        Applicability of Article.............................................................      100

SECTION 1103.        Election to Redeem; Notice to
                       Trustee............................................................................      100


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                                                                                                               PAGE
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SECTION 1104.        Securities to Be Redeemed Pro Rata...................................................      100

SECTION 1105.        Notice of Redemption.................................................................      101

SECTION 1106.        Deposit of Redemption Price..........................................................      102

SECTION 1107.        Securities Payable on Redemption
                       Date...............................................................................      102

SECTION 1108.        Securities Redeemed in Part..........................................................      103


                                 ARTICLE TWELVE

                       Defeasance and Covenant Defeasance

SECTION 1201.        Company's Option to Effect Defeasance
                       or Covenant Defeasance.............................................................      103

SECTION 1202.        Defeasance and Discharge.............................................................      103

SECTION 1203.        Covenant Defeasance  ................................................................      104

SECTION 1204.        Conditions to Defeasance or Covenant
                       Defeasance.........................................................................      104

SECTION 1205.        Deposited Money and U.S. Government
                       Obligations to Be Held in Trust;
                       Other Miscellaneous Provisions.....................................................      107

SECTION 1206.        Reinstatement........................................................................      108

SECTION 1207.        Repayment to Company.................................................................      108

SIGNATURES....................................................................................................  109


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                                     -xii-



                  INDENTURE, dated as of October 1, 1997 between NEXTLINK
Communications, Inc., a corporation organized under the laws of the State of
Washington (the "Company"), having its principal office at 155 108th Avenue
N.E., 8th Floor, Bellevue, Washington 98004, and United States Trust Company of
New York, duly organized and existing under the laws of the State of New York,
as Trustee (herein called the "Trustee").

                             RECITALS OF THE COMPANY

                  The Company has duly authorized the creation of an issue of
$400,000,000 aggregate principal amount of its 9 5/8% Senior Notes Due 2007 (the
"Securities") of substantially the tenor and amount hereinafter set forth, and
to provide therefor the Company has duly authorized the execution and delivery
of this Indenture.

                  All things necessary to make the Securities, when executed by
the Company and authenticated and delivered hereunder and duly issued by the
Company, the valid obligations of the Company, and to make this Indenture a
valid agreement of the Company, in accordance with their and its terms, have
been done.

                  NOW, THEREFORE, THIS INDENTURE WITNESSETH:

                  For and in consideration of the premises and the purchase of
the Securities by the Holders thereof, it is mutually covenanted and agreed, for
the equal and proportionate benefit of all Holders of the Securities, as
follows:


                                   ARTICLE ONE

                        Definitions and Other Provisions
                             of General Application

SECTION 101.  DEFINITIONS.

                  For all purposes of this Indenture, except as otherwise
expressly provided or unless the context otherwise requires:

                  (1) the terms defined in this Article have the meanings
         assigned to them in this Article and include the plural as well as the
         singular;

                  (2) all other terms used herein which are defined in the Trust
         Indenture Act, either




         directly or by reference therein, have the meanings assigned to 
         them therein;

                  (3) all accounting terms not otherwise defined herein have the
         meanings assigned to them in accordance with generally accepted
         accounting principles (whether or not such is indicated herein) and,
         except as otherwise herein expressly provided, the term "generally
         accepted accounting principles" with respect to any computation
         required or permitted hereunder shall mean such accounting principles
         as are generally accepted as consistently applied by the Company at the
         date of such computation; and

                  (4) the words "herein", "hereof" and "hereunder" and other
         words of similar import refer to this Indenture as a whole and not to
         any particular Article, Section or other subdivision.

                  Certain terms, used principally in Article Six, are defined in
that Article.

                  "Act", when used with respect to any Holder, has the meaning
specified in Section 104.

                  "Acquired Debt" means, with respect to any specified Person,
(i) Debt of any other Person existing at the time such Person merges with or
into or consolidates with or becomes a Restricted Subsidiary of such specified
Person and (ii) Debt secured by a Lien encumbering any asset acquired by such
specified Person, which Debt was not Incurred in anticipation of, and was
outstanding prior to, such merger, consolidation or acquisition.

                  "Affiliate" of any specified Person means any other Person
directly or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person. For the purposes of this definition,
"control" when used with respect to any specified Person means the power to
direct the management and policies of such Person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise;
and the terms "controlling" and "controlled" have meanings correlative to the
foregoing.

                  "Agent Member" means any member of, or participant in, the
Depository.

                  "Asset Disposition" by any Person means any transfer,
conveyance, sale, lease or other disposition by such



                                      -2-



Person or any of its Restricted Subsidiaries (including a consolidation or
merger or other sale of any such Restricted Subsidiary with, into or to another
Person in a transaction in which such Restricted Subsidiary ceases to be a
Restricted Subsidiary of the specified Person, but excluding a disposition by a
Restricted Subsidiary of such Person to such Person or a Wholly-Owned Restricted
Subsidiary of such Person or by such Person to a Wholly-Owned Restricted
Subsidiary of such Person) of (i) shares of Capital Stock or other ownership
interests of a Restricted Subsidiary of such Person (other than as permitted by
the provisions of Section 1008 or pursuant to a transaction in compliance with
Section 801), (ii) substantially all of the assets of such Person or any of its
Restricted Subsidiaries representing a division or line of business (other than
as part of a Permitted Investment) or (iii) other assets or rights of such
Person or any of its Restricted Subsidiaries other than (A) in the ordinary
course of business or (B) that constitutes a Restricted Payment which is
permitted by the provisions of Section 1009; PROVIDED that a transaction
described in clauses (i), (ii) and (iii) shall constitute an Asset Disposition
only if the aggregate consideration for such transfer, conveyance, sale, lease
or other disposition is equal to $5 million or more in any 12-month period.

                  "Attributable Value" means, as to any particular lease under
which any Person is at the time liable other than a Capital Lease Obligation,
and at any date as of which the amount thereof is to be determined, the total
net amount of rent required to be paid by such Person under such lease during
the initial term thereof as determined in accordance with generally accepted
accounting principles, discounted from the last date of such initial term to the
date of determination at a rate per annum equal to the discount rate which would
be applicable to a Capital Lease Obligation with like term in accordance with
generally accepted accounting principles. The net amount of rent required to be
paid under any such lease for any such period shall be the aggregate amount of
rent payable by the lessee with respect to such period after excluding amounts
required to be paid on account of insurance, taxes, assessments, utility,
operating and labor costs and similar charges. In the case of any lease which is
terminable by the lessee upon the payment of penalty, such net amount shall also
include the lesser of the amount of such penalty (in which case no rent shall be
considered as required to be paid under such lease subsequent to the first date
upon which it may be so terminated) or the rent which would otherwise be
required to be paid if such lease is not so terminated. "Attributable Value"
means, as to a Capital Lease Obligation, the principal amount thereof.



                                      -3-



                  "Bank Credit Agreement" means any one or more credit
agreements (which may include or consist of revolving credits) between the
Company or any Restricted Subsidiary of the Company and one or more banks or
other financial institutions providing financing for the business of the Company
and its Restricted Subsidiaries.

                  "Board of Directors" means the board of directors of the
Company.

                  "Board Resolution" means a copy of a resolution certified by
the Secretary or an Assistant Secretary of the Company to have been duly adopted
by the Board of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

                  "Business Day" means each Monday, Tuesday, Wednesday, Thursday
and Friday which is not a day on which banking institutions in The Borough of
Manhattan, The City of New York, New York are authorized or obligated by law or
executive order to close.

                  "Capital Lease Obligation" of any Person means the obligation
to pay rent or other payment amounts under a lease of (or other Debt
arrangements conveying the right to use) real or personal property of such
Person which is required to be classified and accounted for as a capital lease
or a liability on the face of a balance sheet of such Person in accordance with
generally accepted accounting principles (a "Capital Lease"). The stated
maturity of such obligation shall be the date of the last payment of rent or any
other amount due under such lease prior to the first date upon which such lease
may be terminated by the lessee without payment of a penalty. The principal
amount of such obligation shall be the capitalized amount thereof that would
appear on the face of a balance sheet of such Person in accordance with
generally accepted accounting principles.

                  "Capital Stock" of any Person means any and all shares,
interests, participations or other equivalents (however designated) of corporate
stock or other equity participations, including partnership interests, whether
general or limited, of such Person.

                  "Change of Control" has the meaning specified in Section 1016.

                  "Commission" means the Securities and Exchange Commission, as
from time to time constituted, created under the Exchange Act, or, if at any
time after the execution of this instrument such Commission is not existing and
perform-



                                      -4-



ing the duties now assigned to it under the Trust Indenture Act, then the body
performing such duties at such time.

                  "Common Equity" of any Person means Capital Stock of such
Person that is not Disqualified Stock, and a "sale of Common Equity" includes
any sale of Common Equity effected by private sale or public offering.

                  "Company" means the Person named as the "Company" in the first
paragraph of this instrument until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture and thereafter "Company"
shall mean such successor Person.

                  "Company Request" or "Company Order" means a written request
or order signed in the name of the Company by (i) the Chief Executive Officer,
the President, an Executive Vice President or a Vice President of the Company,
and (ii) the Treasurer, Assistant Treasurer or Secretary of the Company, and
delivered to the Trustee.

                  "Consolidated Capital Ratio" of any Person as of any date
means the ratio of (i) the aggregate consolidated principal amount of Debt of
such Person then outstanding to (ii) the aggregate consolidated Capital Stock
(other than Disqualified Stock) and paid-in capital (other than in respect of
Disqualified Stock) of such Person as of such date.

                  "Consolidated Cash Flow Available for Fixed Charges" for any
period means the Consolidated Net Income of the Company and its Restricted
Subsidiaries for such period increased by the sum of (i) Consolidated Interest
Expense of the Company and its Restricted Subsidiaries for such period, plus
(ii) Consolidated Income Tax Expense of the Company and its Restricted
Subsidiaries for such period, plus (iii) the consolidated depreciation and
amortization expense included in the income statement of the Company and its
Restricted Subsidiaries for such period, plus (iv) any non-cash expense related
to the issuance to employees of the Company or any Restricted Subsidiary of the
Company of options to purchase Capital Stock of the Company or such Restricted
Subsidiary, plus (v) any charge related to any premium or penalty paid in
connection with redeeming or retiring any Debt prior to its stated maturity;
PROVIDED, HOWEVER, that there shall be excluded therefrom the Consolidated Cash
Flow Available for Fixed Charges (if positive) of any Restricted Subsidiary of
the Company (calculated separately for such Restricted Subsidiary in the same
manner as provided above for the Company) that is subject to a restriction which
prevents the payment of dividends or the making of distributions to the



                                      -5-



Company or another Restricted Subsidiary of the Company to the extent of such
restriction.

                  "Consolidated Income Tax Expense" for any period means the
consolidated provision for income taxes of the Company and its Restricted
Subsidiaries for such period calculated on a consolidated basis in accordance
with generally accepted accounting principles.

                  "Consolidated Interest Expense" means for any period the
consolidated interest expense included in a consolidated income statement
(excluding interest income) of the Company and its Restricted Subsidiaries for
such period calculated on a consolidated basis in accordance with generally
accepted accounting principles, including without limitation or duplication (or,
to the extent not so included, with the addition of), (i) the amortization of
Debt discounts; (ii) any payments or fees with respect to letters of credit,
bankers' acceptances or similar facilities; (iii) fees with respect to interest
rate swap or similar agreements or foreign currency hedge, exchange or similar
agreements; (iv) Preferred Stock dividends of the Company and its Restricted
Subsidiaries (other than dividends paid in shares of Preferred Stock that is not
Disqualified Stock) declared and paid or payable; (v) accrued Disqualified Stock
dividends of the Company and its Restricted Subsidiaries, whether or not
declared or paid; (vi) interest on Debt guaranteed by the Company and its
Restricted Subsidiaries; and (vii) the portion of any Capital Lease Obligation
paid during such period that is allocable to interest expense.

                  "Consolidated Net Income" for any period means the
consolidated net income (or loss) of the Company and its Restricted Subsidiaries
for such period determined on a consolidated basis in accordance with generally
accepted accounting principles; PROVIDED that there shall be excluded therefrom
(a) the net income (or loss) of any Person acquired by the Company or a
Restricted Subsidiary of the Company in a pooling-of-interests transaction for
any period prior to the date of such transaction, (b) the net income (or loss)
of any Person that is not a Restricted Subsidiary of the Company except to the
extent of the amount of dividends or other distributions actually paid to the
Company or a Restricted Subsidiary of the Company by such Person during such
period, (c) gains or losses on Asset Dispositions by the Company or its
Restricted Subsidiaries, (d) all extraordinary gains and extraordinary losses,
(e) the cumulative effect of changes in accounting principles, (f) non-cash
gains or losses resulting from fluctuations in currency exchange rates, (g) any
non-cash



                                      -6-



gain or loss realized on the termination of any employee pension benefit plan
and (h) the tax effect of any of the items described in clauses (a) through (g)
above; PROVIDED, FURTHER, that for purposes of any determination pursuant to the
provisions of Section 1009 there shall further be excluded therefrom the net
income (but not net loss) of any Restricted Subsidiary of the Company that is
subject to a restriction which prevents the payment of dividends or the making
of distributions to the Company or another Restricted Subsidiary of the Company
to the extent of such restriction.

                  "Consolidated Net Worth" of any Person means the consolidated
stockholders' equity of such Person, determined on a consolidated basis in
accordance with generally accepted accounting principles, less amounts
attributable to Disqualified Stock of such Person; PROVIDED that, with respect
to the Company, adjustments following the date of this Indenture to the
accounting books and records of the Company in accordance with Accounting
Principles Board Opinions Nos. 16 and 17 (or successor opinions thereto) or
otherwise resulting from the acquisition of control of the Company by another
Person shall not be given effect to.

                  "Consolidated Tangible Assets" of any Person means the total
amount of assets (less applicable reserves and other properly deductible items)
which under generally accepted accounting principles would be included on a
consolidated balance sheet of such Person and its Restricted Subsidiaries after
deducting therefrom all goodwill, trade names, trademarks, patents, unamortized
debt discount and expense and other like intangibles, which in each case under
generally accepted accounting principles would be included on such consolidated
balance sheet; PROVIDED that, with respect to the Company, adjustments following
the date of this Indenture to the accounting books and records of the Company in
accordance with Accounting Principles Board Opinions Nos. 16 and 17 (or
successor opinions thereto) or otherwise resulting from the acquisition of
control of the Company by another Person shall not be given effect to.

                  "Corporate Trust Office" means the principal office of the
Trustee in the Borough of Manhattan, The City of New York, New York, at which at
any particular time its corporate trust business shall be administered, which at
the date hereof is located at 114 West 47th Street, New York, New York 10036.

                  "corporation" means a corporation, association, company,
limited liability company, joint-stock company or business trust.



                                      -7-



                  "Debt" means (without duplication), with respect to any
Person, whether recourse is to all or a portion of the assets of such Person and
whether or not contingent, (i) every obligation of such Person for money
borrowed, (ii) every obligation of such Person evidenced by bonds, debentures,
notes or other similar instruments, including any such obligations Incurred in
connection with the acquisition of property, assets or businesses, (iii) every
reimbursement obligation of such Person with respect to letters of credit,
bankers' acceptances or similar facilities issued for the account of such
Person, (iv) every obligation of such Person issued or assumed as the deferred
purchase price of property or services (including securities repurchase
agreements but excluding trade accounts payable or accrued liabilities arising
in the ordinary course of business which are not overdue or which are being
contested in good faith), (v) every Capital Lease Obligation of such Person,
(vi) all Receivables Sales of such Person, together with any obligation of such
Person to pay any discount, interest, fees, indemnities, penalties, recourse,
expenses or other amounts in connection therewith, (vii) all obligations to
redeem Disqualified Stock issued by such Person, (viii) every obligation under
Interest Rate or Currency Protection Agreements of such Person and (ix) every
obligation of the type referred to in clauses (i) through (viii) of another
Person and all dividends of another Person the payment of which, in either case,
such Person has Guaranteed. The "amount" or "principal amount" of Debt at any
time of determination as used herein represented by (a) any Debt issued at a
price that is less than the principal amount at maturity thereof, shall be the
amount of the liability in respect thereof determined in accordance with
generally accepted accounting principles, (b) any Receivables Sale, shall be the
amount of the unrecovered capital or principal investment of the purchaser
(other than the Company or a Wholly-Owned Restricted Subsidiary of the Company)
thereof, excluding amounts representative of yield or interest earned on such
investment, (c) any Disqualified Stock, shall be the maximum fixed redemption or
repurchase price in respect thereof, (d) any Capital Lease Obligation, shall be
determined in accordance with the definition thereof, or (e) any Permitted
Interest Rate or Currency Protection Agreement, shall be zero. In no event shall
Debt include any liability for taxes.

                  "Default" means an event that with the passing of time or the
giving of notice or both shall constitute an Event of Default.

                  "Defaulted Interest" has the meaning specified in Section 307.



                                      -8-



                  "Depositary" means, with respect to the Securities issuable or
issued in whole or in part in the form of one or more Global Securities, DTC for
so long as it shall be a clearing agency registered under the Exchange Act, or
such successor (which shall be a clearing agency registered under the Exchange
Act) as the Company shall designate from time to time in an Officers'
Certificate delivered to the Trustee.

                  "Disqualified Stock" of any Person means any Capital Stock of
such Person which, by its terms (or by the terms of any security into which it
is convertible or for which it is exchangeable), or upon the happening of any
event, matures or is mandatorily redeemable, pursuant to a sinking fund
obligation or otherwise, or is redeemable at the option of the holder thereof,
in whole or in part, on or prior to the final Stated Maturity of the Securities;
PROVIDED, HOWEVER, that any Preferred Stock which would not constitute
Disqualified Stock but for provisions thereof giving holders thereof the right
to require the Company to repurchase or redeem such Preferred Stock upon the
occurrence of a Change of Control occurring prior to the final Stated Maturity
of the Securities shall not constitute Disqualified Stock if the change of
control provisions applicable to such Preferred Stock are no more favorable to
the holders of such Preferred Stock than the provisions applicable to the
Securities contained in Section 1016 and such Preferred Stock specifically
provides that the Company will not repurchase or redeem any such stock pursuant
to such provisions prior to the Company's repurchase of such Securities as are
required to be repurchased pursuant to Section 1016.

                  "DTC" means The Depository Trust Company.

                  "Eagle River" means Eagle River Investments, L.L.C., a limited
liability company formed under the laws of the State of Washington.

                  "Eligible Institution" means a commercial banking institution
that has combined capital and surplus of not less than $500 million or its
equivalent in foreign currency, whose debt is rated "A-3" or higher, "A-" or
higher or "A-" or higher according to Moody's Investors Service, Inc., Standard
& Poor's Ratings Group or Duff & Phelps Credit Rating Co. (or such similar
equivalent rating by at least one "nationally recognized statistical rating
organization" (as defined in Rule 436 under the Securities Act)) respectively,
at the time as of which any investment or rollover therein is made.



                                      -9-



                  "Event of Default" has the meaning specified in Section 501.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended (or any successor act) and the rules and regulations thereunder.

                  "Expiration Date" has the meaning set forth in the definition
of "Offer to Purchase" in this Section 101.

                  "Global Security" means a Security in the form prescribed in
Section 204 evidencing all or part of the Securities, issued to the Depositary
or its nominee, and registered in the name of such Depositary or its nominee.

                  "Government Securities" means direct obligations of, or
obligations guaranteed by, the United States of America for the payment of which
obligations or guarantee the full faith and credit of the United States is
pledged and which have a remaining weighted average life to maturity of not more
than 18 months from the date of Investment therein.

                  "Guarantee" by any Person means any obligation, contingent or
otherwise, of such Person guaranteeing, or having the economic effect of
guaranteeing, any Debt of any other Person (the "primary obligor") in any
manner, whether directly or indirectly, and including, without limitation, any
obligation of such Person, (i) to purchase or pay (or advance or supply funds
for the purchase or payment of) such Debt or to purchase (or to advance or
supply funds for the purchase of) any security for the payment of such Debt,
(ii) to purchase property, securities or services for the purpose of assuring
the holder of such Debt of the payment of such Debt, or (iii) to maintain
working capital, equity capital or other financial statement condition or
liquidity of the primary obligor so as to enable the primary obligor to pay such
Debt (and "Guaranteed", "Guaranteeing" and "Guarantor" shall have meanings
correlative to the foregoing); PROVIDED, HOWEVER, that the Guarantee by any
Person shall not include endorsements by such Person for collection or deposit,
in either case, in the ordinary course of business; and PROVIDED, FURTHER, that
the incurrence by a Restricted Subsidiary of the Company of a lien permitted
under clause (iv) of the second paragraph of Section 1011 shall not be deemed to
constitute a Guarantee by such Restricted Subsidiary of any Purchase Money Debt
of the Company secured thereby.

                  "Holder" means a Person in whose name a Security is registered
in the Security Register.



                                      -10-



                  "Incur" means, with respect to any Debt or other obligation of
any Person, to create, issue, incur (by conversion, exchange or otherwise),
assume, Guarantee or otherwise become liable in respect of such Debt or other
obligation including by acquisition of Subsidiaries or the recording, as
required pursuant to generally accepted accounting principles or otherwise, of
any such Debt or other obligation on the balance sheet of such Person (and
"Incurrence", "Incurred", "Incurrable" and "Incurring" shall have meanings
correlative to the foregoing); PROVIDED, HOWEVER, that a change in generally
accepted accounting principles that results in an obligation of such Person that
exists at such time becoming Debt shall not be deemed an Incurrence of such Debt
and that neither the accrual of interest nor the accretion of original issue
discount shall be deemed an Incurrence of Debt; PROVIDED, FURTHER, HOWEVER, that
the Company may elect to treat all or any portion of revolving credit debt of
the Company or a Subsidiary as being incurred from and after any date beginning
the date the revolving credit commitment is extended to the Company or a
Subsidiary, by furnishing notice thereof to the Trustee, and any borrowings or
reborrowings by the Company or a Subsidiary under such commitment up to the
amount of such commitment designated by the Company as Incurred shall not be
deemed to be new Incurrences of Debt by the Company or such Subsidiary.

                  "Indenture" means this instrument as originally executed or as
it may from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into pursuant to the applicable provisions hereof.

                  "Interest Payment Date" means the Stated Maturity of an
installment of interest on the Securities.

                  "Interest Rate or Currency Protection Agreement" of any Person
means any forward contract, futures contract, swap, option or other financial
agreement or arrangement (including, without limitation, caps, floors, collars
and similar agreements) relating to, or the value of which is dependent upon,
interest rates or currency exchange rates or indices.

                  "Investment" by any Person means any direct or indirect loan,
advance or other extension of credit or capital contribution (by means of
transfers of cash or other property to others or payments for property or
services for the account or use of others, or otherwise) to, or purchase or
acquisition of Capital Stock, bonds, notes, debentures or other securities or
evidence of Debt issued by, any other Person, including any payment on a
Guarantee of any 



                                      -11-



obligation of such other Person, but excluding any loan, advance or extension of
credit to an employee of the Company or any of its Restricted Subsidiaries in
the ordinary course of business, accounts receivable and other commercially
reasonable extensions of trade credit.

                  "Issue Date" means the date on which the Securities are first
authenticated and delivered under this Indenture.

                  "Joint Venture" means a corporation, partnership or other
entity engaged in one or more Telecommunications Businesses as to which the
Company (directly or through one or more Restricted Subsidiaries) exercises
managerial control and in which the Company owns (i) a 50% or greater interest,
or (ii) a 30% or greater interest, together with options or other contractual
rights, exercisable not more than seven years after the Company's initial
Investment in such Joint Venture, to increase its interest to not less than 50%.

                  "Lien" means, with respect to any property or assets, any
mortgage or deed of trust, pledge, hypothecation, assignment, Receivables Sale,
deposit arrangement, security interest, lien, charge, easement (other than any
easement not materially impairing usefulness or marketability), encumbrance,
preference, priority or other security agreement or preferential arrangement of
any kind or nature whatsoever on or with respect to such property or assets
(including, without limitation, any conditional sale or other title retention
agreement having substantially the same economic effect as any of the
foregoing).

                  "Marketable Securities" means: (i) Government Securities; (ii)
any time deposit account, money market deposit and certificate of deposit
maturing not more than 365 days after the date of acquisition issued by, or time
deposit of, an Eligible Institution; (iii) commercial paper maturing not more
than 365 days after the date of acquisition issued by a corporation (other than
an Affiliate of the Company) with a rating, at the time as of which any
investment therein is made, of "P-1" or higher according to Moody's Investors
Service, Inc., "A-1" or higher according to Standard & Poor's Ratings Group or
"A-1" or higher according to Duff & Phelps Credit Rating Co. (or such similar
equivalent rating by at least one "nationally recognized statistical rating
organization" (as defined in Rule 436 under the Securities Act)); (iv) any
banker's acceptances or money market deposit accounts issued or offered by an
Eligible Institution; (v) repurchase obligations with a term of not more than 7
days for




                                      -12-



Government Securities entered into with an Eligible Institution; (vi)
auction-rate preferred stocks of any corporation maturing within 90 days after
the date of acquisition by the Company thereof, having a rating of at least AA
by Standard & Poor's; and (vii) any fund investing exclusively in investments of
the types described in clauses (i) through (vi) above.

                  "Maturity", when used with respect to any Security, means the
date on which the principal of such Security becomes due and payable as therein
or herein provided, whether at the Stated Maturity or by declaration of
acceleration, call for redemption or otherwise.

                  "Net Available Proceeds" from any Asset Disposition by any
Person means cash or readily marketable cash equivalents received (including by
way of sale or discounting of a note, installment receivable or other
receivable, but excluding any other consideration received in the form of
assumption by the acquiror of Debt or other obligations relating to such
properties or assets) therefrom by such Person, net of (i) all legal, title and
recording tax expenses, commissions and other fees and expenses Incurred and all
federal, state, provincial, foreign and local taxes (including taxes payable
upon payment or other distribution of funds from a foreign subsidiary to the
Company or another subsidiary of the Company) required to be accrued as a
liability as a consequence of such Asset Disposition, (ii) all payments made by
such Person or its Restricted Subsidiaries on any Debt which is secured by such
assets in accordance with the terms of any Lien upon or with respect to such
assets or which must by the terms of such Lien, or in order to obtain a
necessary consent to such Asset Disposition or by applicable law, be repaid out
of the proceeds from such Asset Disposition, (iii) all distributions and other
payments made to minority interest holders in Restricted Subsidiaries of such
Person or joint ventures as a result of such Asset Disposition, (iv) appropriate
amounts to be provided by such Person or any Restricted Subsidiary thereof, as
the case may be, as a reserve in accordance with generally accepted accounting
principles against any liabilities associated with such assets and retained by
such Person or any Restricted Subsidiary thereof, as the case may be, after such
Asset Disposition, including, without limitation, liabilities under any
indemnification obligations and severance and other employee termination costs
associated with such Asset Disposition, in each case as determined by the Board
of Directors, in its reasonable good faith judgment evidenced by a Board
Resolution filed with the Trustee; PROVIDED, HOWEVER, that any reduction in such
reserve within twelve months following 

                                      -13-



the consummation of such Asset Disposition will be treated for all purposes of
this Indenture and the Securities as a new Asset Disposition at the time of such
reduction with Net Available Proceeds equal to the amount of such reduction, and
(v) any consideration for an Asset Disposition (which would otherwise constitute
Net Available Proceeds) that is required to be held in escrow pending
determination of whether a purchase price adjustment will be made, but amounts
under this clause (v) shall become Net Available Proceeds at such time and to
the extent such amounts are released to such Person.

                  "Offer to Purchase" means a written offer (the "Offer") sent
by the Company by first class mail, postage prepaid, to each Holder at his
address appearing in the Security Register on the date of the Offer offering to
purchase up to the principal amount of Securities specified in such Offer at the
purchase price specified in such Offer (as determined pursuant to this
Indenture). Unless otherwise required by applicable law, the Offer shall specify
an expiration date (the "Expiration Date") of the Offer to Purchase which shall
be, subject to any contrary requirements of applicable law, not less than 30
days or more than 60 days after the date of such Offer and a settlement date
(the "Purchase Date") for purchase of Securities within five Business Days after
the Expiration Date. The Company shall notify the Trustee at least 15 Business
Days (or such shorter period as is acceptable to the Trustee) prior to the
mailing of the Offer of the Company's obligation to make an Offer to Purchase,
and the Offer shall be mailed by the Company or, at the Company's request, by
the Trustee in the name and at the expense of the Company. The Offer shall
contain information concerning the business of the Company and its Subsidiaries
which the Company in good faith believes will enable such Holders to make an
informed decision with respect to the Offer to Purchase (which at a minimum will
include (i) the most recent annual and quarterly financial statements and
"Management's Discussion and Analysis of Financial Condition and Results of
Operations" contained in the documents required to be filed with the Trustee
pursuant to this Indenture (which requirements may be satisfied by delivery of
such documents together with the Offer), (ii) a description of material
developments in the Company's business subsequent to the date of the latest of
such financial statements referred to in clause (i) (including a description of
the events requiring the Company to make the Offer to Purchase), (iii) if
applicable, appropriate pro forma financial information concerning the Offer to
Purchase and the events requiring the Company to make the Offer to Purchase and
(iv) any other information required by 


                                      -14-


applicable law to be included therein). The Offer shall contain all instructions
and materials necessary to enable such Holders to tender Securities pursuant to
the Offer to Purchase. The Offer shall also state:

                  (a)      the Section of this Indenture pursuant to
         which the Offer to Purchase is being made;

                  (b)      the Expiration Date and the Purchase Date;

                  (c) the aggregate principal amount of the Outstanding
         Securities offered to be purchased by the Company pursuant to the Offer
         to Purchase (including, if less than 100%, the manner by which such has
         been determined pursuant to Section 1013 or 1016) (the "Purchase
         Amount");

                  (d) the purchase price to be paid by the Company for each
         $1,000 aggregate principal amount of Securities accepted for payment
         (as specified pursuant to this Indenture) (the "Purchase Price");

                  (e) that the Holder may tender all or any portion of the
         Securities registered in the name of such Holder and that any portion
         of a Security tendered must be tendered in an integral multiple of
         $1,000 principal amount;

                  (f)      the place or places where Securities are to
         be surrendered for tender pursuant to the Offer to
         Purchase;

                  (g) that interest on any Security not tendered or tendered but
         not purchased by the Company pursuant to the Offer to Purchase will
         continue to accrue;

                  (h) that on the Purchase Date the Purchase Price will become
         due and payable upon each Security being accepted for payment pursuant
         to the Offer to Purchase and that interest thereon shall cease to
         accrue on and after the Purchase Date;

                  (i) that each Holder electing to tender a Security pursuant to
         the Offer to Purchase will be required to surrender such Security at
         the place or places specified in the Offer prior to the close of
         business on the Expiration Date (such Security being, if the Company or
         the Trustee so requires, duly endorsed by, or accompanied by a written
         instrument of transfer in form satisfactory to the Company and the


                                      -15-


         Trustee duly executed by, the Holder thereof or his attorney duly
         authorized in writing);

                  (j) that Holders will be entitled to withdraw all or any
         portion of Securities tendered if the Company (or its Paying Agent)
         receives, not later than the close of business on the Expiration Date,
         a telegram, telex, facsimile transmission or letter setting forth the
         name of the Holder, the principal amount of the Security the Holder
         tendered, the certificate number of the Security the Holder tendered
         and a statement that such Holder is withdrawing all or a portion of his
         tender;

                  (k) that (a) if Securities in an aggregate principal amount
         less than or equal to the Purchase Amount are duly tendered and not
         withdrawn pursuant to the Offer to Purchase, the Company shall purchase
         all such Securities and (b) if Securities in an aggregate principal
         amount in excess of the Purchase Amount are tendered and not withdrawn
         pursuant to the Offer to Purchase, the Company shall purchase
         Securities having an aggregate principal amount equal to the Purchase
         Amount on a pro rata basis (with such adjustments as may be deemed
         appropriate so that only Securities in denominations of $1,000 or
         integral multiples thereof shall be purchased);

                  (l) that in the case of any Holder whose Security is purchased
         only in part, the Company shall execute, and the Trustee shall
         authenticate and deliver to the Holder of such Security without service
         charge, a new Security or Securities, of any authorized denomination as
         requested by such Holder, in an aggregate principal amount equal to and
         in exchange for the unpurchased portion of the Security so tendered;
         and

                  (m) the CUSIP number or numbers of the Securities offered to
         be purchased by the Company pursuant to the Offer to Purchase.

Any Offer to Purchase shall be governed by and effected in accordance with the
Offer for such Offer to Purchase.

                  "Officers' Certificate" means a certificate signed by (i) the
Chief Executive Officer, President, an Executive Vice President or a Vice
President, and (ii) the Treasurer, Assistant Treasurer, Secretary or an
Assistant Secretary, of the Company, and delivered to the Trustee and containing
the statements provided for in Section 102. One of the officers signing an
Officers' Certificate given pursuant to 



                                      -16-


Section 1018 shall be the principal executive, financial or accounting officer
of the Company.

                  "Opinion of Counsel" means a written opinion of legal counsel,
who may be counsel for the Company, and who shall be acceptable to the Trustee,
and containing the statements provided for in Section 102.

                  "Outstanding", when used with respect to Securities, means, as
of the date of determination, all Securities theretofore authenticated and
delivered under this Indenture, EXCEPT:

                (i)  Securities theretofore cancelled by the
         Trustee or delivered to the Trustee for
         cancellation;

               (ii) Securities for whose payment or redemption money in the
         necessary amount has been theretofore deposited with the Trustee or any
         Paying Agent (other than the Company) in trust or set aside and
         segregated in trust by the Company (if the Company shall act as its own
         Paying Agent) for the Holders of such Securities; PROVIDED that, if
         such Securities are to be redeemed, notice of such redemption has been
         duly given pursuant to this Indenture; and

              (iii) Securities which have been paid pursuant to Section 306 or
         in exchange for or in lieu of which other Securities have been
         authenticated and delivered pursuant to this Indenture, other than any
         such Securities in respect of which there shall have been presented to
         the Trustee proof satisfactory to it that such Securities are held by a
         bona fide purchaser in whose hands such Securities are valid
         obligations of the Company;

PROVIDED, HOWEVER, that in determining whether the Holders of the requisite
principal amount of the Outstanding Securities have given any request, demand,
authorization, direction, notice, consent or waiver hereunder, Securities owned
by the Company or any other obligor upon the Securities or any Affiliate of the
Company or of such other obligor shall be disregarded and deemed not to be
Outstand ing, except that, in determining whether the Trustee shall be protected
in relying upon any such request, demand, authorization, direction, notice,
consent or waiver, only Securities which the Trustee knows to be so owned shall
be so disregarded. Securities so owned which have been pledged in good faith may
be regarded as Outstanding if the pledgee 




                                      -17-


establishes to the satisfaction of the Trustee the pledgee's right so to act
with respect to such Securities and that the pledgee is not the Company or any
other obligor upon the Securities or any Affiliate of the Company or of such
other obligor.

                  "Paying Agent" means any Person authorized by the Company to
pay the principal of (and premium, if any) or interest on any Securities on
behalf of the Company. The Trustee is hereby authorized by the Company to act as
a "Paying Agent" for the purposes of this Indenture, until such time as the
Company notifies the Trustee in writing that such authorization is revoked.

                  "Permitted Interest Rate or Currency Protection Agreement" of
any Person means any Interest Rate or Currency Protection Agreement entered into
with one or more financial institutions in the ordinary course of business that
is designed to protect such Person against fluctuations in interest rates or
currency exchange rates with respect to Debt Incurred and which shall have a
notional amount no greater than the payments due with respect to the Debt being
hedged thereby and not for purposes of speculation.

                  "Permitted Investment" means (i) any Investment in a Joint
Venture (including the purchase or acquisition of any Capital Stock of a Joint
Venture), provided the aggregate amount of all outstanding Investments pursuant
to this clause (i) in Joint Ventures in which the Company owns, directly or
indirectly, a less than 50% interest shall not exceed $25 million, (ii) any
Investment in any Person as a result of which such Person becomes a Restricted
Subsidiary, or, subject to the proviso to clause (i) of this definition, becomes
a Joint Venture of the Company, (iii) any Investment in Marketable Securities,
(iv) Investments in Permitted Interest Rate or Currency Protection Agreements,
and (v) Investments made as a result of the receipt of noncash consideration
from an Asset Disposition that was made pursuant to and in compliance with
Section 1013 of this Indenture.

                  "Permitted Liens" means (a) Liens for taxes, assessments,
governmental charges or claims which are not yet delinquent or which are being
contested in good faith by appropriate proceedings, if a reserve or other
appropriate provision, if any, as shall be required in conformity with generally
accepted accounting principles shall have been made therefor; (b) other Liens
incidental to the conduct of the Company's and its Restricted Subsidiaries'
business or the ownership of its property and assets not securing any Debt, and
which do not in the aggregate materially detract 



                                      -18-


from the value of the Company's and its Restricted Subsidiaries' property or
assets when taken as a whole, or materially impair the use thereof in the
operation of its business; (c) Liens with respect to assets of a Restricted
Subsidiary granted by such Restricted Subsidiary to the Company to secure Debt
owing to the Company; (d) pledges and deposits made in the ordinary course of
business in connection with workers' compensation, unemployment insurance and
other types of statutory obligations (including to secure government contracts);
(e) deposits made to secure the performance of tenders, bids, leases, and other
obligations of like nature incurred in the ordinary course of business
(exclusive of obligations for the payment of borrowed money); (f) zoning
restrictions, servitudes, easements, rights-of-way, restrictions and other
similar charges or encumbrances incurred in the ordinary course of business
which, in the aggregate, do not materially detract from the value of the
property subject thereto or interfere with the ordinary conduct of the business
of the Company or its Restricted Subsidiaries; (g) Liens arising out of
judgments or awards against the Company or any Restricted Subsidiary with
respect to which the Company or such Restricted Subsidiary is prosecuting an
appeal or proceeding for review and the Company or such Restricted Subsidiary is
maintaining adequate reserves in accordance with generally accepted accounting
principles; (h) any interest or title of a lessor in the property subject to any
lease other than a Capital Lease; and (i) any statutory warehousemen's,
materialmen's or other similar Liens for sums not then due and payable (or
which, if due and payable, are being contested in good faith and with respect to
which adequate reserves are being maintained to the extent required by generally
accepted accounting principles).

                  "Person" means any individual, corporation, partnership,
limited liability company, joint venture, association, joint stock company,
trust, unincorporated organization, government or agency or political
subdivision thereof or any other entity.

                  "Predecessor Security" of any particular Security means every
previous Security issued before, and evidencing all or a portion of the same
debt as that evidenced by, such particular Security; and, for the purposes of
this definition, any Security authenticated and delivered under Section 306 in
exchange for or in lieu of a mutilated, destroyed, lost or stolen Security shall
be deemed to evidence the same debt as the mutilated, destroyed, lost or stolen
Security.




                                      -19-


                  "Preferred Dividends" for any Person means for any period the
quotient determined by dividing the amount of dividends and distributions paid
or accrued (whether or not declared) on Preferred Stock of such Person during
such period calculated in accordance with generally accepted accounting
principles, by 1 minus the maximum statutory income tax rate then applicable to
the Company (expressed as a decimal).

                  "Preferred Stock" of any Person means Capital Stock of such
Person of any class or classes (however designated) that ranks prior, as to the
payment of dividends or as to the distribution of assets upon any voluntary or
involuntary liquidation, dissolution or winding up of such Person, to shares of
Capital Stock of any other class of such Person.

                  "Purchase Date" has the meaning set forth in the definition of
"Offer to Purchase" in this Section 101.

                  "Purchase Money Debt" means (i) Acquired Debt Incurred in
connection with the acquisition of Telecommunications Assets and (ii) Debt of
the Company or of any Restricted Subsidiary of the Company (including, without
limitation, Debt represented by Capital Lease Obligations, Vendor Financing
Facilities, mortgage financings and purchase money obligations) Incurred for the
purpose of financing all or any part of the cost of construction, acquisition or
improvement by the Company or any Restricted Subsidiary of the Company or any
Joint Venture of any Telecommunications Assets of the Company, any Restricted
Subsidiary of the Company or any Joint Venture, and including any related notes,
Guarantees, collateral documents, instruments and agreements executed in
connection therewith, as the same may be amended, supplemented, modified or
restated from time to time.

                  "readily marketable cash equivalents" means (i) marketable
securities issued or directly and unconditionally guaranteed by the United
States Government or issued by any agency thereof and backed by the full faith
and credit of the United States; (ii) marketable direct obligations issued by
any state of the United States of America or any political subdivision of any
such state or any public instrumentality thereof and, at the time of
acquisition, having the highest rating obtainable from either Standard & Poor's
Rating Group or Moody's Investors Service, Inc.; (iii) commercial paper maturing
no more than 180 days from the date of acquisition thereof and, at the time of
acquisition, having a rating of P-1 according to Moody's Investors Service,
Inc., "A-1" or higher according to Standard & 



                                      -20-


Poor's Ratings Group or "A-1" or higher according to Duff & Phelps Credit Rating
Co. (or such similar equivalent rating by at least one "nationally recognized
statistical rating organization" (as defined in Rule 436 under the Securities
Act)); and (iv) certificates of deposit or bankers' acceptance maturing within
one year from the date of acquisition thereof issued by any commercial bank
organized under the laws of the United States of America or any state thereof or
the District of Columbia having unimpaired capital and surplus of not less than
$100,000,000.

                  "Receivables" means receivables, chattel paper, instruments,
documents or intangibles evidencing or relating to the right to payment of money
in respect of the sale of goods or services.

                  "Receivables Sale" of any Person means any sale of Receivables
of such Person (pursuant to a purchase facility or otherwise), other than in
connection with a disposition of the business operations of such Person relating
thereto or a disposition of defaulted Receivables for purpose of collection and
not as a financing arrangement.

                  "Redemption Date", when used with respect to any Security to
be redeemed, means the date fixed for such redemption by or pursuant to this
Indenture.

                  "Redemption Price", when used with respect to any Security to
be redeemed, means the price at which it is to be redeemed pursuant to this
Indenture.

                  "Regular Record Date" for the interest payable on any Interest
Payment Date means the September 15 or March 15 (whether or not a Business Day),
as the case may be, next preceding such Interest Payment Date.

                  "Related Person" of any Person means any other Person directly
or indirectly owning (a) 10% or more of the Outstanding Common Equity of such
Person (or, in the case of a Person that is not a corporation, 10% or more of
the equity interest in such Person) or (b) 10% or more of the combined voting
power of the Voting Stock of such Person.

                  "Responsible Officer", when used with respect to the Trustee,
means the chairman or any vice-chairman of the board of directors, the chairman
or any vice-chairman of the executive committee of the board of directors, the
chairman of the trust committee, the president, any vice president, the
secretary, any assistant secretary, the treasurer, any assistant treasurer, the
cashier, any assistant cashier, any trust officer or assistant trust officer,
the controller or 



                                      -21-


any assistant controller or any other officer of the Trustee customarily
performing functions similar to those performed by any of the above designated
officers and also means, with respect to a particular corporate trust matter,
any other officer to whom such matter is referred because of his knowledge of
and familiarity with the particular subject.

                  "Restricted Subsidiary" of the Company means any Subsidiary,
whether existing on or after the date of this Indenture, unless such Subsidiary
is an Unrestricted Subsidiary.

                  "Sale and Leaseback Transaction" of any Person means an 
arrangement with any lender or investor or to which such lender or investor 
is a party providing for the leasing by such Person of any property or asset 
of such Person which has been or is being sold or transferred by such Person 
more than 365 days after the acquisition thereof or the completion of 
construction or commencement of operation thereof to such lender or investor 
or to any person to whom funds have been or are to be advanced by such lender 
or investor on the security of such property or asset. The stated maturity of 
such arrangement shall be the date of the last payment of rent or any other 
amount due under such arrangement prior to the first date on which such 
arrangement may be terminated by the lessee without payment of a penalty.

                  "SEC Reports" has the meaning specified in Section
704.

                  "Securities" has the meaning specified in the
second paragraph of this instrument.

                  "Securities Act" means the Securities Act of 1933 and any
statute successor thereto, in each case as amended from time to time.

                  "Security Register" and "Security Registrar" have the
respective meanings specified in Section 305(b).

                  "Significant Subsidiary" means a Restricted Subsidiary that is
a "significant subsidiary" as defined in Rule 1-02(w) of Regulation S-X under
the Securities Act and the Exchange Act.

                  "Special Record Date" for the payment of any Defaulted
Interest means a date fixed by the Trustee pursuant to Section 307.


                                      -22-


                  "Stated Maturity", when used with respect to any Security or
any installment of interest thereon, means the date specified in such Security
as the fixed date on which the principal of such Security or such installment of
interest, as the case may be, is due and payable.

                  "Subordinated Debt" means Debt of the Company as to which the
payment of principal of (and premium, if any) and interest and other payment
obligations in respect of such Debt shall be subordinate to the prior payment in
full of the Securities to at least the following extent: (i) no payments of
principal of (or premium, if any) or interest on or otherwise due in respect of
such Debt may be permitted for so long as any default in the payment of
principal (or premium, if any) or interest on the Securities exists; (ii) in the
event that any other default that with the passing of time or the giving of
notice, or both, would constitute an Event of Default exists with respect to the
Securities, upon notice by 25% or more in principal amount of the Securities to
the Trustee, the Trustee shall have the right to give notice to the Company and
the holders of such Debt (or trustees or agents therefor) of a payment blockage,
and thereafter no payments of principal of (or premium, if any) or interest on
or otherwise due in respect of such Debt may be made for a period of 179 days
from the date of such notice or for the period until such default has been cured
or waived or ceased to exist and any acceleration of the Securities has been
rescinded or annulled, whichever period is shorter (which Debt may provide that
(A) no new period of payment blockage may be commenced by a payment blockage
notice unless and until 360 days have elapsed since the effectiveness of the
immediately prior notice, (B) no nonpayment default that existed or was
continuing on the date of delivery of any payment blockage notice to such
holders (or such agents or trustees) shall be, or be made, the basis for a
subsequent payment blockage notice and (C) failure of the Company to make
payment on such Debt when due or within any applicable grace period, whether or
not on account of such payment blockage provisions, shall constitute an event of
default thereunder); and (iii) such Debt may not (x) provide for payments of
principal of such Debt at the stated maturity thereof or by way of a sinking
fund applicable thereto or by way of any mandatory redemption, defeasance,
retirement or repurchase thereof by the Company (including any redemption,
retirement or repurchase which is contingent upon events or circumstances, but
excluding any retirement required by virtue of acceleration of such Debt upon an
event of default thereunder), in each case prior to the final Stated Maturity of
the Securities or (y) permit redemption or other retirement (including pursuant
to an offer to purchase made by the Company) of such other Debt at the option of
the holder thereof prior to the final Stated Maturity of the Securities, other
than a redemption or other retirement at the option of the holder of such Debt
(including pursuant to an offer to purchase made 



                                      -23-


by the Company) which is conditioned upon a change of control of the Company
pursuant to provisions substantially similar to those of Section 1016 (and which
shall provide that such Debt will not be repurchased pursuant to such provisions
prior to the Company's repurchase of the Securities required to be repurchased
by the Company pursuant to the provisions of Section 1016.

                  "Subsidiary" of any Person means (i) a corporation more than
50% of the combined voting power of the outstanding Voting Stock of which is
owned, directly or indirectly, by such Person or by one or more other
Subsidiaries of such Person or by such Person and one or more Subsidiaries
thereof or (ii) any other Person (other than a corporation) in which such
Person, or one or more other Subsidiaries of such Person or such Person and one
or more other Subsidiaries thereof, directly or indirectly, has at least a
majority ownership and power to direct the policies, management and affairs
thereof.

                  "Successor Security" of any particular Security means every
Security issued after, and evidencing all or a portion of the same debt as that
evidenced by, such particular Security; and, for the purposes of this
definition, any Security authenticated and delivered under Section 306 in
exchange for or in lieu of a mutilated, destroyed, lost or stolen Security shall
be deemed to evidence the same debt as the mutilated, destroyed, lost or stolen
Security.

                  "Telecommunications Assets" means all assets, rights
(contractual or otherwise) and properties, whether tangible or intangible, used
or intended for use in connection with a Telecommunications Business.

                  "Telecommunications Business" means the business of (i)
transmitting, or providing services relating to the transmission of, voice,
video or data through owned or leased transmission facilities, (ii) creating,
developing or marketing communications related network equipment, software and
other devices for use in a Telecommunication Business or (iii) evaluating,
participating or pursuing any other activity or opportunity that is primarily
related to those identified in (i) or (ii) above and shall, in any event,
include all businesses in which the Company or any of its Subsidiaries are
engaged on the Issue Date; PROVIDED that 



                                      -24-


the determination of what constitutes a Telecommunications Business shall be
made in good faith by the Board of Directors, which determination shall be
conclusive.

                  "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean such successor Trustee.

                  "Trust Indenture Act" means the Trust Indenture Act of 1939 as
in force at the date as of which this instrument was executed; PROVIDED,
HOWEVER, that in the event the Trust Indenture Act of 1939 is amended after such
date, "Trust Indenture Act" means, to the extent required by any such amendment,
the Trust Indenture Act of 1939 as so amended.

                  "Unrestricted Subsidiary" means (1) any Subsidiary
of the Company designated as such by the Board of Directors as set forth below
where (a) neither the Company nor any of its other Subsidiaries (other than
another Unrestricted Subsidiary) (i) provides credit support for, or Guarantee
of, any Debt of such Subsidiary or any Subsidiary of such Subsidiary (including
any undertaking, agreement or instrument evidencing such Debt) or (ii) is
directly or indirectly liable for any Debt of such Subsidiary or any Subsidiary
of such Subsidiary, and (b) no default with respect to any Debt of such
Subsidiary or any Subsidiary of such Subsidiary (including any right which the
holders thereof may have to take enforcement action against such Subsidiary)
would permit (upon notice, lapse of time or both) any holder of any other Debt
of the Company and its Restricted Subsidiaries to declare a default on such
other Debt or cause the payment thereof to be accelerated or payable prior to
its final scheduled maturity and (2) any Subsidiary of an Unrestricted
Subsidiary. The Board of Directors may designate any Subsidiary to be an
Unrestricted Subsidiary unless such Subsidiary owns any Capital Stock of, or
owns or holds any Lien on any property of, any other Subsidiary of the Company
which is not a Subsidiary of the Subsidiary to be so designated or otherwise an
Unrestricted Subsidiary, PROVIDED that either (x) the Subsidiary to be so
designated has total assets of $1,000 or less or (y) immediately after giving
effect to such designation, the Company could Incur at least $1.00 of additional
Debt pursuant to the first paragraph of Section 1007 and PROVIDED, FURTHER, that
the Company could make a Restricted Payment in an amount equal to the greater of
the fair market value and the book value of such Subsidiary pursuant to Section
1009 and such amount is thereafter treated as a 



                                      -25-


Restricted Payment for the purpose of calculating the aggregate amount available
for Restricted Payments thereunder. The Board of Directors may designate any
Unrestricted Subsidiary to be a Restricted Subsidiary, PROVIDED that,
immediately after giving effect to such designation, the Company could Incur at
least $1.00 of additional Debt pursuant to the first paragraph of Section 1007.

                  "Vendor Financing Facility" means any agreements between the
Company or a Restricted Subsidiary of the Company and one or more vendors or
lessors of equipment to the Company or any of its Restricted Subsidiaries (or
any affiliate of any such vendor or lessor) providing financing for the
acquisition by the Company or any such Restricted Subsidiary of equipment from
any such vendor or lessor.

                  "Vice President", when used with respect to the Company or the
Trustee, means any vice president, whether or not designated by a number or a
word or words added before or after the title "vice president".

                  "Voting Stock" of any Person means Capital Stock of such
Person which ordinarily has voting power for the election of directors (or
persons performing similar functions) of such Person, whether at all times or
only so long as no senior class of securities has such voting power by reason of
any contingency.

                  "Wholly-Owned Restricted Subsidiary" of any Person means a
Restricted Subsidiary of such Person 99% or more of the outstanding Capital
Stock or other ownership interests of which (other than directors' qualifying
shares) shall at the time be owned by such Person or by one or more Wholly-
Owned Restricted Subsidiaries of such Person or by such Person and one or more
Wholly-Owned Restricted Subsidiaries of such Person.


SECTION 102.  COMPLIANCE CERTIFICATES AND OPINIONS.

                  Upon any application or request by the Company to the Trustee
to take any action under any provision of this Indenture, the Company shall
furnish to the Trustee such certificates and opinions as may be required under
the Trust Indenture Act and under this Indenture. Each such certificate or
opinion shall be given in the form of an Officers' Certificate, if to be given
by an officer of the Company, or an Opinion of Counsel, if to be given by
counsel, and shall comply with the requirements of the Trust Indenture Act and
any other requirement set forth in this Indenture.



                                      -26-


                  Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include

                  (1) a statement that each individual signing such certificate
         or opinion has read such covenant or condition and the definitions
         herein relating thereto;

                  (2) a brief statement as to the nature and scope of the
         examination or investigation upon which the statements or opinions
         contained in such certificate or opinion are based;

                  (3) a statement that, in the opinion of each such individual,
         he has made such examination or investigation as is necessary to
         enable him to express an informed opinion as to whether or not such
         covenant or condition has been complied with; and

                  (4) a statement as to whether, in the opinion of each such
         individual, such condition or covenant has been complied with.


SECTION 103.  FORM OF DOCUMENTS DELIVERED TO TRUSTEE.

                  In any case where several matters are required to be certified
by, or covered by an opinion of, any specified Person, it is not necessary that
all such matters be certif ied by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

                  Any certificate of an officer of the Company may be based,
insofar as it relates to legal matters, upon an opinion of counsel submitted
therewith, unless such officer knows, or in the exercise of reasonable care
should know, that the opinion with respect to the matters upon which his
certificate is based is erroneous. Any opinion of counsel may be based, insofar
as it relates to factual matters, upon a certificate of an officer or officers
of the Company submitted therewith stating the information on which counsel is
relying, unless such counsel knows, or in the exercise of



                                      -27-


reasonable care should know, that the certificate with respect to such matters
is erroneous.

                  Where any Person is required to make, give or execute two or
more applications, requests, consents, certificates, statements, opinions or
other instruments under this Indenture, they may, but need not, be consolidated
and form one instrument.


SECTION 104.  ACTS OF HOLDERS; RECORD DATES.

                  Any request, demand, authorization, direction, notice,
consent, waiver or other action provided by this Indenture to be given or taken
by Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agent duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments are delivered
to the Trustee and, where it is hereby expressly required, to the Company. Such
instrument or instruments (and the action embodied therein and evidenced
thereby) are herein sometimes referred to as the "Act" of the Holders signing
such instrument or instruments. Proof of execution of any such instrument or of
a writing appointing any such agent shall be sufficient for any purpose of this
Indenture and (subject to Section 601) conclusive in favor of the Trustee and
the Company, if made in the manner provided in this Section.

                  The fact and date of the execution by any Person of any such
instrument or writing pursuant to this Section 104 may be proved by the
affidavit of a witness of such execution or by a certificate of a notary public
or other officer authorized by law to take acknowledgments of deeds, certifying
that the individual signing such instrument or writing acknowledged to him the
execution thereof. Where such execution is by a signer acting in a capacity
other than his individual capacity, such certificate or affidavit shall also
constitute sufficient proof of his authority. The fact and date of the execution
of any such instrument or writing, or the authority of the Person executing the
same, may also be proved in any other manner which the Trustee deems sufficient.

                  The ownership of Securities shall be proved by the Security
Register.

                  Any request, demand, authorization, direction, notice,
consent, waiver or other Act of the Holder of any Security shall bind every
future Holder of the same Security 



                                      -28-


and the Holder of every Security issued upon the registration of transfer
thereof or in exchange therefor or in lieu thereof in respect of anything done,
omitted or suffered to be done by the Trustee or the Company in reliance
thereon, whether or not notation of such action is made upon such Security.

                  The Company may set any day as a record date for the purpose
of determining the Holders of Outstanding Securities entitled to give, make or
take any request, demand, authorization, direction, notice, consent, waiver or
other action provided or permitted by this Indenture to be given, made or taken
by Holders of Securities, PROVIDED that the Company may not set a record date
for, and the provisions of this paragraph shall not apply with respect to, the
giving or making of any notice, declaration, request or direction referred to in
the next paragraph. If not set by the Company prior to the first solicitation of
a Holder made by any Person in respect of any such matter referred to in the
foregoing sentence, the record date for any such matter shall be the 30th day
(or, if later, the date of the most recent list of Holders required to be
provided pursuant to Section 701) prior to such first solicitation. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities on such record date, and no other Holders, shall be entitled to take
the relevant action, whether or not such Holders remain Holders after such
record date; PROVIDED that no such action shall be effective hereunder unless
taken on or prior to the applicable Expiration Date by Holders of the requisite
principal amount of Outstanding Securities on such record date. Nothing in this
paragraph shall be construed to prevent the Company from setting a new record
date for any action for which a record date has previously been set pursuant to
this paragraph (whereupon the record date previously set shall automatically and
with no action by any Person be cancelled and of no effect), and nothing in this
paragraph shall be construed to render ineffective any action taken by Holders
of the requisite principal amount of Outstanding Securities on the date such
action is taken. Promptly after any record date is set pursuant to this
paragraph, the Company, at its own expense, shall cause notice of such record
date, the proposed action by Holders and the applicable Expiration Date to be
given to the Trustee in writing and to each Holder of Securities in the manner
set forth in Section 106.

                  The Trustee may set any day as a record date for the purpose
of determining the Holders of Outstanding Securities entitled to join in the
giving or making of (i) any Notice of Default, (ii) any declaration of
acceleration referred to in Section 502, (iii) any request to 



                                      -29-


institute proceedings referred to in Section 507(2) or (iv) any direction
referred to in Section 512. If any record date is set pursuant to this
paragraph, the Holders of Outstanding Securities on such record date, and no
other Holders, shall be entitled to join in such notice, declaration, request or
direction, whether or not such Holders remain Holders after such record date;
PROVIDED that no such action shall be effective hereunder unless taken on or
prior to the applicable Expiration Date by Holders of the requisite principal
amount of Outstanding Securities on such record date. Nothing in this paragraph
shall be construed to prevent the Trustee from setting a new record date for any
action for which a record date has previously been set pursuant to this
paragraph (whereupon the record date previously set shall automatically and with
no action by any Person be cancelled and of no effect), and nothing in this
paragraph shall be construed to render ineffective any action taken by Holders
of the requisite principal amount of Outstanding Securities on the date such
action is taken. Promptly after any record date is set pursuant to this
paragraph, the Trustee, at the Company's expense, shall cause notice of such
record date, the proposed action by Holders and the applicable Expiration Date
to be given to the Company in writing and to each Holder of Securities in the
manner set forth in Section 106.

                  With respect to any record date set pursuant to this Section,
the party hereto which sets such record dates may designate any day as the
"Expiration Date" and from time to time may change the Expiration Date to any
earlier or later day; PROVIDED that no such change shall be effective unless
notice of the proposed new Expiration Date is given to the other party hereto in
writing, and to each Holder of Securities in the manner set forth in Section
106, on or prior to the existing Expiration Date. If an Expiration Date is not
designated with respect to any record date set pursuant to this Section, the
party hereto which set such record date shall be deemed to have initially
designated the 180th day after such record date as the Expiration Date with
respect thereto, subject to its right to change the Expiration Date as provided
in this paragraph. Notwithstanding the foregoing, no Expiration Date shall be
later than the 180th day after the applicable record date.

                  Without limiting the foregoing, a Holder entitled hereunder to
take any action hereunder with regard to any particular Security may do so with
regard to all or any part of the principal amount of such Security or by one or
more duly appointed agents each of which may do so pursuant to such appointment
with regard to all or any part of such principal amount.


                                      -30-


SECTION 105.  NOTICES, ETC., TO TRUSTEE AND COMPANY.

                  Any request, demand, authorization, direction, notice,
consent, waiver or Act of Holders or other document provided or permitted by
this Indenture to be made upon, given or furnished to, or filed with,

                  (1)  the Trustee by any Holder or by the Company
         shall be sufficient for every purpose hereunder if
         delivered in writing to the Trustee at its Corporate
         Trust Office, Attention: Corporate Trust
         Administration, or

                  (2) the Company by the Trustee or by any Holder shall be
         sufficient for every purpose hereunder (unless otherwise herein
         expressly provided) if in writing and mailed, first-class postage
         prepaid, to the Company addressed to the Company at the address of its
         principal office specified in the first paragraph of this instrument or
         at any other address previously furnished in writing to the Trustee by
         the Company.


SECTION 106.  NOTICE TO HOLDERS; WAIVER.

                  Where this Indenture provides for notice to Holders of any
event, such notice shall be sufficiently given (unless otherwise herein
expressly provided) if (i) in the case of a Global Security, in writing by
facsimile and/or by overnight mail to the Depositary, and (ii) in the case of
securities other than Global Securities, in writing and mailed, first-class
postage prepaid, to each Holder affected by such event, at his address as it
appears in the Security Register, not later than the latest date (if any), and
not earlier than the earliest date (if any), prescribed for the giving of such
notice. In any case where notice to Holders is given by mail, neither the
failure to mail such notice, nor any defect in any notice so mailed, to any
particular Holder shall affect the sufficiency of such notice with respect to
other Holders. Where this Indenture provides for notice in any manner, such
notice may be waived in writing by the Person entitled to receive such notice,
either before or after the event, and such waiver shall be the equivalent of
such notice. Waivers of notice by Holders shall be filed with the Trustee, but
such filing shall not be a condition precedent to the validity of any action
taken in reliance upon such waiver.

                  In case by reason of the suspension of regular mail service or
by reason of any other cause it shall be 



                                      -31-


impracticable to give such notice by mail, then such notifi cation as shall be
made with the approval of the Trustee shall constitute a sufficient notification
for every purpose hereunder.


SECTION 107.  CONFLICT WITH TRUST INDENTURE ACT.

                  The Trust Indenture Act shall apply as a matter of contract to
this Indenture for purposes of interpretation, construction and defining the
rights and obligations here under. If any provision hereof limits, qualifies or
conflicts with a provision of the Trust Indenture Act that is required under
such Act to be a part of and govern this Indenture, the latter provision shall
control. If any provision of this Indenture modifies or excludes any provision
of the Trust Indenture Act that may be so modified or excluded, the latter
provision shall be deemed to apply to this Indenture as so modified or to be
excluded, as the case may be.


SECTION 108.  EFFECT OF HEADINGS AND TABLE OF CONTENTS.

                  The Article and Section headings herein and the Table of
Contents are for convenience only and shall not affect the construction hereof.


SECTION 109.  SUCCESSORS AND ASSIGNS.

                  All covenants and agreements in this Indenture by the Company
shall bind its successors and assigns, whether so expressed or not.


SECTION 110.  SEPARABILITY CLAUSE.

                  In case any provision in this Indenture or in the Securities
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.


SECTION 111.  BENEFITS OF INDENTURE.

                  Nothing in this Indenture or in the Securities, express or
implied, shall give to any Person, other than the parties hereto and their
successors hereunder and the 



                                      -32-


Holders of Securities, any benefit or any legal or equitable right, remedy or
claim under this Indenture.


SECTION 112.  GOVERNING LAW.

                  This Indenture and the Securities shall be governed by and
construed in accordance with the laws of the State of New York.

SECTION 113.  LEGAL HOLIDAYS.

                  In any case where any Interest Payment Date, Redemption Date,
Purchase Date or Stated Maturity of any Security shall not be a Business Day,
then (notwithstanding any other provision of this Indenture or of the
Securities) payment of interest or principal (and premium, if any) need not be
made on such date, but may be made on the next succeeding Business Day with the
same force and effect as if made on the Interest Payment Date, Redemption Date,
Purchase Date or at the Stated Maturity, PROVIDED that no interest shall accrue
for the period from and after such Interest Payment Date, Redemption Date,
Purchase Date or Stated Maturity, as the case may be.


                                   ARTICLE TWO

                                 Security Forms

SECTION 201.  FORMS GENERALLY.

                  The Securities and the Trustee's certificates of
authentication thereof shall be in substantially the forms set forth in this
Article, with such appropriate legends, insertions, omissions, substitutions and
other variations as are required or permitted by this Indenture, and may have
such letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with the rules of any
securities exchange or as may, consistently herewith, be determined by the
officers executing such Securities, as evidenced by their execution of the
Securities.

                  The definitive Securities shall be printed, lithographed or
engraved or produced by any combination of these methods on steel engraved
borders or may be produced in any other manner, all as determined by the
officers executing such Securities, as evidenced by their execution of such
Securities.

                                      -33-


                  In certain cases described elsewhere herein, the legends set
forth in Section 202 may be omitted from Securities issued hereunder.


SECTION 202.  FORM OF FACE OF SECURITY.

                  [If the Security is a Global Security, insert the
legends required by Section 204 of the Indenture]



                          NEXTLINK Communications, Inc.

                           9 5/8% SENIOR NOTES DUE 2007


                                                       CUSIP NUMBER: 65333H AA 1
No.                                                             $               
    ------                                                       ---------------

                  NEXTLINK Communications, Inc., a corporation organized under
the laws of the State of Washington (herein called the "Company", which term
includes any successor Person under the Indenture hereinafter referred to), for
value received, hereby promises to pay to Cede & Co., or registered assigns, the
principal sum of _____________ Dollars on October 1, 2007, and to pay interest
thereon from October 1, 1997 or from the most recent Interest Payment Date to
which interest has been paid or duly provided for, semi-annually on October 1,
and April 1 in each year, commencing April 1, 1998 at the rate of 9 5/8% per
annum, until the principal hereof is paid or made available for payment. The
interest so payable, and punctually paid or duly provided for, on any Interest
Payment Date will, as provided in such Indenture, be paid to the Person in whose
name this Security (or one or more Predecessor Securities) is registered at the
close of business on the Regular Record Date for such interest, which shall be
September 15 or March 15 (whether or not a Business Day), as the case may be,
next preceding such Interest Payment Date. Any such interest not so punctually
paid or duly provided for will forthwith cease to be payable to the Holder on
such Regular Record Date and may either be paid to the Person in whose name this
Security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice whereof shall be given to Holders of Securities
not less than 10 days prior to such Special Record Date, or be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities may be listed, and upon such notice
as may be 



                                      -34-


required by such exchange, all as more fully provided in said Indenture.

                  In the case of a default in payment of principal and premium,
if any, upon acceleration or redemption, interest shall be payable pursuant to
the preceding paragraph on such overdue principal (and premium, if any), such
interest shall be payable on demand and, if not so paid on demand, such interest
shall itself bear interest at the rate of 1% per annum (to the extent that the
payment of such interest shall be legally enforceable), and shall accrue from
the date of such demand for payment to the date payment of such interest has
been made or duly provided for, and such interest on unpaid interest shall also
be payable on demand.

                  If this Security is issued in the form of a Global Security,
payments of the principal of (and premium, if any) and interest on this Security
shall be made in immediately available funds to the Depositary. If this Security
is issued in certificated form, payment of the principal of (and premium, if
any) and interest on this Security will be made at the corporate trust office of
the Trustee and at the office or agency of the Company maintained for that
purpose in the Borough of Manhattan, The City of New York, New York, and at any
other office or agency maintained by the Company for such purpose, in such coin
or currency of the United States of America as at the time of payment is legal
tender for payment of public and private debts; PROVIDED, HOWEVER, that at the
option of the Company payment of interest may be made by check mailed to the
address of the Person entitled thereto as such address shall appear in the
Security Register.

                  Reference is hereby made to the further provisions of this
Security set forth on the reverse hereof, which further provisions shall for all
purposes have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee referred to on the reverse hereof by manual signature,
this Security shall not be entitled to any benefit under the Indenture or be
valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

Dated: October 1, 1997.



                                      -35-


                                            NEXTLINK Communications, Inc.



                                            By
                                              ------------------------------
                                              Name: Charles P. Daniels
                                              Title: Vice President
Attest:



- ------------------------------
Name: R. Bruce Easter, Jr.
Title: Vice President, General
           Counsel & Secretary



SECTION 203.  FORM OF REVERSE OF SECURITY.

                  This Security is one of a duly authorized issue of Securities
of the Company designated as its 95/8% Senior Notes Due 2007 (the "Securities")
issued under an Indenture, dated as of October 1, 1997 (herein called the
"Indenture"), between the Company and United States Trust Company of New York,
as trustee (herein called the "Trustee", which term includes any successor
trustee under the Indenture). The Securities are limited in aggregate principal
amount to $400,000,000. Reference is hereby made to the Indenture and all
indentures supplemental thereto for a statement of the respective rights,
limitations of rights, duties and immunities thereunder of the Company, the
Trustee and the Holders of the Securities and of the terms upon which the
Securities are, and are to be, authenticated and delivered.

                  The Securities are subject to redemption upon not less than 30
nor more than 60 days' notice by mail to each Holder of Securities to be
redeemed at such Holder's address appearing in the Security Register, in amounts
of $1,000 or an integral multiple of $1,000, at any time on or after October 1,
2002 and prior to maturity, as a whole or in part, at the election of the
Company, at the following Redemption Prices (expressed as percentages of the
principal amount) plus accrued and unpaid interest to but excluding the
Redemption Date (subject to the right of Holders of record on the relevant
Regular Record Date to receive interest due on an Interest Payment that is on or
prior to the Redemption Date), if redeemed during the 12-month period beginning
October 1, of each of the years indicated below:




                                      -36-




                                         Redemption
                Year                       Price
                ----                     ----------
                                           
                2002                     104.813%
                2003                     103.208%
                2004                     101.604%


and thereafter at a Redemption Price equal to 100.000% of the principal amount,
together in the case of any such redemption with accrued interest to the
Redemption Date, but interest installments whose Stated Maturity is on or prior
to such Redemption Date will be payable to the Holders of such Securities, or
one or more Predecessor Securities, of record at the close of business on the
relevant Record Dates referred to on the face hereof, all as provided in the
Indenture.

                  The Securities are further subject to redemption prior to
October 1, 2002 only in the event that on or before October 1, 2000 the Company
receives net proceeds from a sale of its Common Equity, in which case the
Company may, at its option, use all or a portion of any such net proceeds to
redeem Securities in a principal amount of up to an aggregate amount equal to
33 1/3% of the original principal amount of the Securities, PROVIDED, HOWEVER,
that Securities in an amount equal to at least $266.7 million remain Outstanding
after such redemption. Such redemption must occur on a Redemption Date within 90
days of any such sale and upon not less than 30 nor more than 60 days' notice by
mail to each Holder of Securities to be redeemed at such Holder's address
appearing in the Security Register, in amounts of $1,000 or an integral multiple
of $1,000 at a Redemption Price of 109.625% of their principal amount plus
accrued and unpaid interest, if any, to but excluding the Redemption Date
(subject to the right of Holders of record on the relevant Regular Record Date
to receive interest due on an Interest Payment Date that is on or prior to the
Redemption Date).

                  In the event of redemption of this Security in part only, a
new Security or Securities for the unredeemed portion hereof will be issued in
the name of the Holder hereof upon the cancellation hereof.

                  The Securities do not have the benefit of any sinking fund
obligations.

                  The Indenture provides that, subject to certain
conditions, if (i) a Change of Control occurs or (ii)

                                      -37-



certain Net Available Proceeds are available to the Company as a result of any
Asset Disposition, the Company shall be required to make an Offer to Purchase
for all or a specified portion of the Securities.

                  In the event of redemption or purchase pursuant to an Offer to
Purchase of this Security in part only, a new Security or Securities of like
tenor for the unredeemed or unpurchased portion hereof will be issued in the
name of the Holder hereof upon the cancellation hereof.

                  If an Event of Default shall occur and be continuing, the
principal of all the Securities may be declared due and payable in the manner
and with the effect provided in the Indenture.

                  The Indenture contains provisions for defeasance at any time
of (i) the entire indebtedness of this Security, or (ii) certain restrictive
covenants and Events of Default with respect to this Security, in each case upon
compliance with certain conditions set forth therein.

                  The Indenture permits, with certain exceptions as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holders of the Securities under
the Indenture at any time by the Company and the Trustee with the consent of the
Holders of a majority in aggregate principal amount of the Securities at the
time Outstanding. The Indenture also contains provisions permitting the Holders
of specified percentages in aggregate principal amount of the Securities at the
time Outstanding, on behalf of the Holders of all the Securities, to waive
compliance by the Company with certain provisions of the Indenture and certain
past defaults under the Indenture and their consequences. Any such consent or
waiver by the Holder of this Security shall be conclusive and binding upon such
Holder and upon all future Holders of this Security and of any Security issued
upon the registration of transfer hereof or in exchange herefor or in lieu
hereof, whether or not notation of such consent or waiver is made upon this
Security.

                  As provided in and subject to the provisions of the Indenture,
the Holder of this Security shall not have the right to institute any proceeding
with respect to the Indenture or for the appointment of a receiver or trustee or
for any other remedy thereunder, unless such Holder shall have previously given
the Trustee written notice of a continuing Event of Default, the Holders of not
less than 25% in principal amount of the Outstanding Securities shall have made
written request to the Trustee to institute 


                                      -38-



proceedings in respect of such Event of Default as Trustee and offered the
Trustee reasonable indemnity, and the Trustee shall not have received from the
Holders of a majority in principal amount of Outstanding Securities a direction
inconsistent with such request, and shall have failed to institute any such
proceeding, for 60 days after receipt of such notice, request and offer of
indemnity. The foregoing shall not apply to any suit instituted by the Holder of
this Security for the enforcement of any payment of principal hereof or any
premium or interest hereon on or after the respective due dates expressed
herein.

                  No reference herein to the Indenture and no provision of this
Security or of the Indenture shall alter or impair the obligation of the
Company, which is absolute and unconditional, to pay the principal of (and
premium, if any) and interest on this Security at the times, place and rate, and
in the coin or currency, herein prescribed.

                  As provided in the Indenture and subject to certain
limitations therein set forth, the transfer of this Security is registrable in
the Security Register, upon surrender of this Security for registration of
transfer at the office or agency of the Company in the Borough of Manhattan, The
City of New York, New York, duly endorsed by, or accompanied by a written
instrument of transfer in form satisfactory to the Company and the Security
Registrar duly executed by, the Holder hereof or his attorney duly authorized
in writing, and thereupon one or more new Securities, of authorized
denominations and like tenor and for the same aggregate principal amount, will
be issued to the designated transferee or transferees.

                  The Securities are issuable only in registered form without
coupons in denominations of $1,000 and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations therein set forth,
Securities are exchangeable for a like tenor and aggregate principal amount of
Securities of a different authorized denomination, as requested by the Holder
surrendering the same.

                  No service charge shall be made for any such registration of
transfer or exchange, but the Company may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  Prior to due presentment of this Security for registration of
transfer, the Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name this Security is registered as the owner
hereof for all purposes, whether or not this Security be overdue, 


                                      -39-



and none of the Company, the Trustee or any such agent shall be affected by
notice to the contrary.

                  Interest on this Security shall be computed on the basis of a
360-day year of twelve 30-day months.

                  All terms used in this Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

                       OPTION OF HOLDER TO ELECT PURCHASE

                  If you want to elect to have this Security purchased in its
entirety by the Company pursuant to Section 1013 or 1016 of the Indenture, check
the box:

                                      / /

                  If you want to elect to have only a part of this Security
purchased by the Company pursuant to Section 1013 or 1016 of the Indenture,
state the amount: $___________



Dated:                              Your Signature
      ----------------                             -----------------------------
                                         (Sign exactly as name
                                         appears on the other side of
                                         this Security)




Signature Guarantee:
                     -----------------------------------------------------------
                     Notice: Signature(s) must be guaranteed by an
                     "eligible guarantor institution" meeting the
                     requirements of the Trustee, which requirements will
                     include membership or participation in STAMP or such
                     other "signature guarantee program" as may be
                     determined by the Trustee in addition to, or in
                     substitution for STAMP, all in accordance with the
                     Securities Exchange Act of 1934, as amended.


                                      -40-



SECTION 204. ADDITIONAL PROVISIONS REQUIRED IN GLOBAL SECURITY.

                  Any Global Security issued hereunder shall, in addition to the
provisions contained in Sections 202 and 203, bear a legend in substantially the
following form:

                  [If a Global Security, insert -- THIS SECURITY IS A GLOBAL
SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS
REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF. THIS SECURITY MAY
NOT BE EXCHANGED IN WHOLE OR IN PART FOR A SECURITY REGISTERED, AND NO TRANSFER
OF THIS SECURITY IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY
PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED
CIRCUMSTANCES DESCRIBED IN THE INDENTURE.]

                  [If a Global Security to be held by the Depository Trust
Company, insert -- UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"),
TO ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE, OR PAYMENT, AND
ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER
NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS
MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY A PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE
& CO., HAS AN INTEREST HEREIN.]

SECTION 205. FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION.

                  This is one of the Securities referred to in the
within-mentioned Indenture.


                  United States Trust Company of New York,
                                                         as Trustee


                                   By
                                      ------------------------------------------
                                      Authorized Signatory



                                      -41-


                                  ARTICLE THREE

                                 The Securities

SECTION 301.  TITLE AND TERMS.

                  The aggregate principal amount of Securities which may be
authenticated and delivered under this Indenture is limited to $400,000,000,
except for Securities authenticated and delivered upon registration of transfer
of, or in exchange for, or in lieu of, other Securities pursuant to Section 304,
305, 306, 906 or 1108 or in connection with an Offer to Purchase pursuant to
Section 1013 or 1016.

                  The Securities shall be known and designated as the "95/8%
Senior Notes Due 2007" of the Company. The Stated Maturity of the Securities
shall be October 1, 2007. The Securities shall bear interest at the rate of
95/8% per annum, from October 1, 1997 or from the most recent Interest Payment
Date thereafter to which interest has been paid or duly provided for, as the
case may be, payable semi-annually on October 1 and April 1, commencing April 1,
1998, until the principal thereof is paid or made available for payment.

                  In the case of a default in payment of principal and premium,
if any, upon acceleration or redemption, interest shall be payable pursuant to
the preceding paragraph on such overdue principal (and premium, if any), such
interest shall be payable on demand and, if not so paid on demand, such interest
shall itself bear interest at the rate of 1% per annum (to the extent that the
payment of such interest shall be legally enforceable), and shall accrue from
the date of such demand for payment to the date payment of such interest has
been made or duly provided for, and such interest on unpaid interest shall also
be payable on demand.

                  If this Security is issued in the form of a Global Security,
payments of the principal of (and premium, if any) and interest on this Security
shall be made in immediately available funds to the Depositary. If the
Securities are issued in certificated form, the principal of and premium, if
any, and interest on the Securities shall be payable at the corporate trust
office of the Trustee in the Borough of Manhattan, The City of New York, New
York, maintained for such purpose and at any other office or agency maintained
by the Company for such purpose; PROVIDED, HOWEVER, that at the option of the
Company payment of interest may be made by check mailed to the address of the
Person entitled thereto as such address shall appear in the Security Register.


                                      -42-


                  The Securities shall be subject to repurchase by the Company
pursuant to an Offer to Purchase as provided in Sections 1013 and 1016.

                  The Securities shall be redeemable as provided in Article
Eleven.

                  The Securities shall not have the benefit of any sinking fund
obligations.

                  The Securities shall be subject to defeasance at the option of
the Company as provided in Article Twelve.


SECTION 302.  DENOMINATIONS.

                  The Securities are issuable only in registered form without
coupons in denominations of $1,000 and any integral multiple thereof.


SECTION 303. EXECUTION, AUTHENTICATION, DELIVERY AND DATING.

                  The Securities shall be executed on behalf of the Company by
its Chief Executive Officer, its President, its Executive Vice President or one
of its Vice Presidents and attested by its Secretary. The signature of any of
these officers on the Securities may be manual or facsimile.

                  Securities bearing the manual or facsimile signatures of
individuals who were at any time the proper officers of the Company shall bind
the Company, notwithstanding that such individuals or any of them have ceased
to hold such offices prior to the authentication and delivery of such Securities
or did not hold such offices at the date of such Securities.

                  At any time and from time to time after the execution and
delivery of this Indenture, the Company may deliver Securities executed by the
Company to the Trustee for authentication, together with a Company Order for the
authentication and delivery of such Securities; and the Trustee in accordance
with such Company Order shall authenticate and deliver such Securities as in
this Indenture provided and not otherwise.

                  Each Security shall be dated the date of its authentication.


                                      -43-



                  No Security shall be entitled to any benefit under this
Indenture or be valid or obligatory for any purpose unless there appears on such
Security a certificate of authentication substantially in the form provided for
herein executed by the Trustee by manual signature, and such certificate upon
any Security shall be conclusive evidence, and the only evidence, that such
Security has been duly authenticated and delivered hereunder.

SECTION 304.  TEMPORARY SECURITIES.

                  Pending the preparation of definitive Securities, the Company
may execute, and upon a Company Order the Trustee shall authenticate and
deliver, temporary Securities which are printed, lithographed, typewritten,
mimeographed or otherwise produced, in any authorized denomination,
substantially of the tenor of the definitive Securities in lieu of which they
are issued and with such appropriate insertions, omissions, substitutions and
other variations as the officers executing such Securities may determine, as
evidenced by their execution of such Securities.

                  If temporary Securities are issued, the Company will cause
definitive Securities to be prepared without unreasonable delay. After the
preparation of definitive Securities, the temporary Securities shall be
exchangeable for definitive Securities upon surrender of the temporary
Securities at any office or agency of the Company designated pursuant to Section
1002, without charge to the Holder. Upon surrender for cancellation of any one
or more temporary Securities, the Company shall execute and the Trustee shall
authenticate and deliver in exchange therefor a like tenor and principal amount
of definitive Securities of authorized denominations. Until so exchanged, the
temporary Securities shall in all respects be entitled to the same benefits
under this Indenture as definitive Securities.


SECTION 305. REGISTRATION, REGISTRATION OF TRANSFER AND EXCHANGE.

                  The Company shall cause to be kept at the Corporate Trust
Office of the Trustee a register (the register maintained in such office and in
any other office or agency designated pursuant to Section 1002 being herein
sometimes collectively referred to as the "Security Register") in which, subject
to such reasonable regulations as they may prescribe, the Company shall provide
for the registration of Securities and of transfers and exchanges of Securities.
The Trustee is hereby appointed "Security Registrar" for the 


                                      -44-


purpose of registering Securities and transfers and exchanges of Securities as
herein provided. Such Security Register shall distinguish between Original
Securities and Exchange Securities.

                  Upon surrender for registration of transfer of any Security at
an office or agency of the Company designated pursuant to Section 1002 for such
purpose, the Company shall execute, and the Trustee shall authenticate and
deliver, in the name of the designated transferee or transferees, one or more
new Securities of any authorized denominations and of a like tenor and aggregate
principal amount and bearing the applicable legends set forth in Section 202.

                  At the option of the Holder, Securities may be exchanged for
other Securities of any authorized denomina tions and of a like tenor and
aggregate principal amount and bearing the applicable legends set forth in
Section 202, upon surrender of the Securities to be exchanged at such office or
agency. Whenever any Securities are so surrendered for exchange, the Company
shall execute, and the Trustee shall authenticate and deliver, the Securities
which the Holder making the exchange is entitled to receive.

                  All Securities issued upon any registration of transfer or
exchange of Securities shall be the valid obligations of the Company, evidencing
the same debt, and entitled to the same benefits under this Indenture, as the
Securities surrendered upon such registration of transfer or exchange.

                  Every Security presented or surrendered for regis tration of
transfer or for exchange shall (if so required by the Company or the Trustee) be
duly endorsed, or be accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed, by the
Holder thereof or his attorney duly authorized in writing.

                  No service charge shall be made to the Holder for any
registration of transfer or exchange of Securities, but the Company may require
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in connection with any registration of transfer or exchange of
Securities, other than exchanges pursuant to Section 304, 906 or 1108 or in
accordance with any Offer to Purchase pursuant to Section 1013 or 1016 not
involving any transfer.

                  The Company shall not be required (i) to issue, register the
transfer of or exchange any Security during a period beginning at the opening of
business 15 days before 


                                      -45-


the day of the mailing of a notice of redemption of Securities selected for
redemption under Section 1104 and ending at the close of business on the day of
such mailing, or (ii) to register the transfer of or exchange any Security so
selected for redemption in whole or in part, except the unredeemed portion of
any Security being redeemed in part.

                  The provisions of Clauses (1), (2), (3) and (4) below shall
apply only to Global Securities:

                  (1) Each Global Security authenticated under this Indenture
         shall be registered in the name of the Depositary designated for such
         Global Security or a nominee thereof and delivered to such Depositary
         or a nominee thereof or custodian therefor, and each such Global
         Security shall constitute a single Security for all purposes of this
         Indenture.

                  (2) Notwithstanding any other provisions in this Indenture, no
         Global Security may be exchanged in whole or in part for Securities
         registered, and no transfer of a Global Security in whole or in part
         may be registered, in the name of any Person other than the Depositary
         for such Global Security or a nominee thereof unless (A) such
         Depositary (i) has notified the Company that it is unwilling or unable
         to continue as Depositary for such Global Security or (ii) has ceased
         to be a clearing agency registered under the Exchange Act, or (B) there
         shall have occurred and be continuing an Event of Default with respect
         to such Global Security.

                  (3) Subject to Clause (2) above, any exchange of a Global
         Security for other Securities may be made in whole or in part, and all
         Securities issued in exchange for a Global Security or any portion
         thereof shall be registered in such names as the Depositary for such
         Global Security shall direct.

                  (4) Every Security authenticated and delivered upon
         registration of transfer of, or in exchange for or in lieu of, a Global
         Security or any portion thereof, whether pursuant to this Section,
         Section 304, 306, 906 or 1108 or otherwise, shall be authenticated and
         delivered in the form of, and shall be, a Global Security, unless such
         Security is registered in the name of a Person other than the
         Depositary for such Global Security or a nominee thereof.


                                      -46-


SECTION 306. MUTILATED, DESTROYED, LOST AND STOLEN SECURITIES.

                  If any mutilated Security is surrendered to the Trustee, the
Company shall execute and the Trustee shall authenticate and deliver in exchange
therefor a new Security of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

                  If there shall be delivered to the Company and the Trustee (i)
evidence to their satisfaction of the destruction, loss or theft of any
Security and (ii) such security or indemnity as may be required by them to save
each of them and any agent of either of them harmless, then, in the absence of
notice to the Company or the Trustee that such Security has been acquired by a
bona fide purchaser, the Company shall execute and the Trustee shall
authenticate and deliver, in lieu of any such destroyed, lost or stolen
Security, a new Security of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

                  In case any such mutilated, destroyed, lost or stolen Security
has become or is about to become due and payable, the Company in the discretion
of the Company may, instead of issuing a new Security, pay such Security.

                  Upon the issuance of any new Security under this Section, the
Company may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

                  Every new Security issued pursuant to this Section in lieu of
any destroyed, lost or stolen Security shall constitute an original additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security shall be at any time enforceable by anyone, and shall be
entitled to all the benefits of this Indenture equally and proportionately with
any and all other Securities duly issued hereunder.

                  The provisions of this Section are exclusive and shall
preclude (to the extent lawful) all other rights and remedies with respect to
the replacement or payment of mutilated, destroyed, lost or stolen Securities.


                                      -47-



SECTION 307. PAYMENT OF INTEREST; INTEREST RIGHTS PRESERVED.

                  Interest on any Security which is payable, and is punctually
paid or duly provided for, on any Interest Payment Date shall be paid to the
Person in whose name that Security (or one or more Predecessor Securities) is
registered at the close of business on the Regular Record Date for such
interest.

                  Any interest on any Security which is payable, but is not
punctually paid or duly provided for, on any Interest Payment Date (herein
called "Defaulted Interest") shall (a) bear interest at the rate per annum
stated in the form of Security included herein (to the extent that the payment
of such interest shall be legally enforceable), and (b) forthwith cease to be
payable to the Holder on the relevant Regular Record Date by virtue of having
been such Holder, and such Defaulted Interest may be paid by the Company, at its
election in each case, as provided in Clause (1) or (2) below:

                  (1) The Company may elect to make pay ment of any Defaulted
         Interest to the Persons in whose names the Securities (or their
         respective Predecessor Securities) are registered at the close of
         business on a Special Record Date for the payment of such Defaulted
         Interest, which shall be fixed in the following manner. The Company
         shall notify the Trustee in writing of the amount of Defaulted Interest
         proposed to be paid on each Security and the date of the proposed
         payment, and at the same time the Company shall deposit with the
         Trustee an amount of money equal to the aggregate amount proposed to be
         paid in respect of such Defaulted Interest or shall make arrangements
         satisfactory to the Trustee for such deposit prior to the date of the
         proposed payment, such money when deposited to be held in trust for the
         benefit of the Persons entitled to such Defaulted Interest as in this
         Clause provided. Thereupon the Trustee shall fix a Special Record Date
         for the payment of such Defaulted Interest which shall be not more than
         15 days and not less than 10 days prior to the date of the proposed
         payment and not less than 10 days after the receipt by the Trustee of
         the notice of the proposed payment. The Trustee shall promptly notify
         the Company of such 


                                      -48-


         Special Record Date and, in the name and at the expense of the Company,
         shall cause notice of the proposed payment of such Defaulted Interest
         and the Special Record Date therefor to be mailed, first-class postage
         prepaid, to each Holder at his address as it appears in the Security
         Register, not less than 10 days prior to such Special Record Date.
         Notice of the proposed payment of such Defaulted Interest and the
         Special Record Date therefor having been so mailed, such Defaulted
         Interest shall be paid to the Persons in whose names the Securities (or
         their respective Predecessor Securities) are registered at the close of
         business on such Special Record Date and shall no longer be payable
         pursuant to the following Clause (2).

                  (2) The Company may make payment of any Defaulted Interest in
         any other lawful manner not inconsistent with the requirements of any
         securities exchange on which the Securities may be listed, and upon
         such notice as may be required by such exchange, if, after notice given
         by the Company to the Trustee of the proposed payment pursuant to this
         Clause, such manner of payment shall be deemed practicable by the
         Trustee.

                  Subject to the foregoing provisions of this Section, each
Security delivered under this Indenture upon registration of transfer of or in
exchange for or in lieu of any other Security shall carry the rights to interest
accrued and unpaid, and to accrue, which were carried by such other Security.


SECTION 308.  PERSONS DEEMED OWNERS.

                  Prior to due presentment of a Security for registration of
transfer, the Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name such Security is registered as the owner of
such Security for the purpose of receiving payment of principal of and premium,
if any, and (subject to Section 307) interest on such Security and for all other
purposes whatsoever, whether or not such Security be overdue, and none of the
Company, the Trustee or any agent of the Company or the Trustee shall be
affected by notice to the contrary.


                                      -49-


SECTION 309.  CANCELLATION.

                  All Securities surrendered for payment, redemp tion,
registration of transfer, exchange or pursuant to any Offer to Purchase pursuant
to Section 1013 or 1016 shall, if surrendered to any Person other than the
Trustee, be delivered to the Trustee and shall be promptly cancelled by it. The
Company may at any time deliver to the Trustee for cancellation any Securities
previously authenticated and delivered hereunder which the Company may have
acquired in any manner whatsoever, and all Securities so delivered shall be
promptly cancelled by the Trustee. No Securities shall be authenticated in lieu
of or in exchange for any Securities cancelled as provided in this Section,
except as expressly permitted by this Indenture. All cancelled Securities held
by the Trustee shall be disposed of in accordance with its standard procedures
or as directed by a Company Order; PROVIDED, HOWEVER, that the Trustee shall not
be required to destroy such Securities.


SECTION 310.  COMPUTATION OF INTEREST.

                  Interest on the Securities shall be computed on the basis of a
360-day year of twelve 30-day months.


SECTION 311.  CUSIP NUMBERS.

                  The Company shall in issuing the Securities use CUSIP numbers,
and the Trustee shall use the applicable CUSIP number in notices of redemption
or exchange as a convenience to the Holders; PROVIDED, that any such notice may
state that no representation is made as to the accuracy of correctness of the
CUSIP number or numbers printed in the notice or on the certificates
representing the Securities and that reliance may be placed only on the other
identification numbers printed on the certificates representing the Securities.


                                  ARTICLE FOUR

                           Satisfaction and Discharge

SECTION 401.  SATISFACTION AND DISCHARGE OF INDENTURE.

                  This Indenture shall cease to be of further effect as to all
outstanding Securities (except as to (i) rights of registration of transfer and
exchange and the Company's right of optional redemption, (ii) substitution of


                                      -50-



apparently mutilated, defaced, destroyed, lost or stolen Securities, (iii)
rights of holders of Securities to receive payment of principal of and premium,
if any, and interest on the Securities, (iv) rights, obligations and immunities
of the Trustee under this Indenture and (v) rights of the holders of the
Securities as beneficiaries of this Indenture with respect to any property
deposited with the Trustee payable to all or any of them), and the Trustee, on
demand of and at the expense of the Company, shall execute proper instruments
acknowledging satisfaction and discharge of this Indenture, when

                  (1) either

                           (A) the Company will have paid or caused to be paid
                  the principal of and premium, if any, and interest on the
                  Securities as and when the same will have become due and
                  payable; or

                           (B) all outstanding Securities (except lost, stolen
                  or destroyed Securities which have been replaced or paid) have
                  been delivered to the Trustee for cancellation;

                  and the Company, in the case of (A) above, has deposited or
                  caused to be deposited with the Trustee as trust funds in
                  trust for the purpose an amount sufficient to pay and
                  discharge the entire indebtedness on such Securities not
                  theretofore delivered to the Trustee for cancellation, for
                  principal of and premium, if any, and interest to the date of
                  such deposit (in the case of Securities which have become due
                  and payable) or to the Stated Maturity or Redemption Date, as
                  the case may be;

                  (2) the Company has paid or caused to be paid all other sums
         payable hereunder by the Company;

                  (3) the Company has delivered to the Trustee an Officers'
         Certificate and an Opinion of Counsel, each stating that all conditions
         precedent herein provided for relating to the satisfaction and
         discharge of this Indenture have been complied with; and

                  (4) the Trustee shall have received such other documents and
         assurances as the Trustee shall have reasonably requested.

Notwithstanding the satisfaction and discharge of this Indenture, (i) the
obligations of the Company to the Trustee 


                                      -51-


under Section 607, (ii) substitution of apparently mutilated, defaced,
destroyed, lost or stolen Securities, (iii) rights of holders of Securities to
receive payment of principal of and premium, if any, and interest on the
Securities, (iv) rights, obligations and immunities of the Trustee under this
Indenture (including, if money shall have been deposited with the Trustee
pursuant to subclause (B) of Clause (1) of this Section, the obligations of the
Trustee under Section 402 and the last paragraph of Section 1003), and (v)
rights of holders of the Securities as beneficiaries of this Indenture with
respect to any property deposited with the Trustee payable to all or any of
them, shall survive.


SECTION 402.  APPLICATION OF TRUST MONEY.

                  Subject to the provisions of the last paragraph of Section
1003, all money deposited with the Trustee pursuant to Section 401 shall be held
in trust and applied by it, in accordance with the provisions of the Securities
and this Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Persons entitled thereto, of the principal (and premium, if
any) and interest for whose payment such money has been deposited with the
Trustee.


                                  ARTICLE FIVE

                                    Remedies

SECTION 501.  EVENTS OF DEFAULT.

                  "Event of Default", wherever used herein, means any one of the
following events (whatever the reason for such Event of Default and whether it
shall be voluntary or involuntary or be effected by operation of law or pursuant
to any judgment, decree or order of any court or any order, rule or regulation
of any administrative or governmental body):

                  (1) default in the payment of any interest upon any Security
         when it becomes due and payable, and continuance of such default for a
         period of 30 days; or

                  (2) default in the payment of the principal of (or premium, if
         any, on) any Security when due; or



                                      -52-


                  (3) default in the payment of principal and interest upon any
         Security required to be purchased pursuant to an Offer to Purchase
         pursuant to Sections 1013 or 1016 when due and payable; or

                  (4) default in the performance, or breach, of Section 801; or

                  (5) default in the performance, or breach, of any covenant or
         warranty of the Company in this Indenture or in any Security (other
         than a covenant or warranty a default in whose performance or whose
         breach is elsewhere in this Section specifically dealt with), and
         continuance of such default or breach for a period of 60 days after
         there has been given, by registered or certified mail, to the Company
         by the Trustee or to the Company and the Trustee by the Holders of at
         least 25% in aggregate principal amount of the Outstanding Securities a
         written notice specifying such default or breach and requiring it to be
         remedied and stating that such notice is a "Notice of Default"
         hereunder; or

                  (6) a default or defaults under any bond(s), debenture(s),
         note(s) or other evidence(s) of Debt by the Company or any Significant
         Subsidiary of the Company or under any mortgage(s), indenture(s) or
         instrument(s) under which there may be issued or by which there may be
         secured or evidenced any Debt of such type by the Company or any such
         Significant Subsidiary with a principal amount then outstanding,
         individually or in the aggregate, in excess of $10 million, whether
         such Debt now exists or shall hereafter be created, which default or
         defaults shall constitute a failure to pay such Debt when due at the
         final maturity thereof, or shall have resulted in such Debt becoming or
         being declared due and payable prior to the date on which it would
         otherwise have become due and payable; or

                  (7) a final judgment or final judgments (not subject to
         appeal) for the payment of money are entered against the Company or any
         Significant Subsidiary in an aggregate amount in excess of $10 million
         by a court or courts of competent jurisdiction, which judgments remain
         undischarged or unstayed for a period (during which execution shall not
         be effectively stayed) of 45 days after the right to appeal all such
         judgments has expired; or

                  (8) the entry by a court having jurisdiction in the premises
         of (A) a decree or order for relief in 


                                      -53-


         respect of the Company or any Significant Subsidiary in an involuntary
         case or proceeding under any applicable Federal or State bankruptcy,
         insolvency, reorganization or other similar law or (B) a decree or
         order adjudging the Company or any Significant Subsidiary a bankrupt or
         insolvent, or approving as properly filed a petition seeking
         reorganization, arrangement, adjustment or composition of or in respect
         of the Company or any Significant Subsidiary under any applicable
         Federal or State law, or appointing a custodian, receiver, liquidator,
         assignee, trustee, sequestrator or other similar official of the
         Company or any Significant Subsidiary or of any substantial part of its
         property, or ordering the winding up or liquidation of its affairs, and
         the continuance of any such decree or order for relief or any such
         other decree or order unstayed and in effect for a period of 60
         consecutive days; or

                  (9) the commencement by the Company or any Significant
         Subsidiary of a voluntary case or proceeding under any applicable
         Federal or State bankruptcy, insolvency, reorganization or other
         similar law or of any other case or proceeding to be adjudicated a
         bankrupt or insolvent, or the consent by it to the entry of a decree or
         order for relief in respect of the Company or any Significant
         Subsidiary in an involuntary case or proceeding under any applicable
         Federal or State bankruptcy, insolvency, reorganization or other
         similar law or to the commencement of any bankruptcy or insolvency case
         or proceeding against it, or the filing by it of a petition or answer
         or consent seeking reorganization or relief under any applicable
         Federal or State law, or the consent by it to the filing of such
         petition or to the appointment of or taking possession by a custodian,
         receiver, liquidator, assignee, trustee, sequestrator or other similar
         official of the Company or any Significant Subsidiary or of any
         substantial part of its property, or the making by it of an assignment
         for the benefit of creditors, or the admission by it in writing of its
         inability to pay its debts generally as they become due, or the taking
         of corporate action by the Company or any Significant Subsidiary in
         furtherance of any such action.


                                      -54-


SECTION 502. ACCELERATION OF MATURITY; RESCISSION AND ANNULMENT.

                  If an Event of Default (other than an Event of Default
specified in Section 501(8) or (9) with respect to the Company) occurs and is
continuing, then and in every such case the Trustee or the Holders of not less
than 25% in aggregate principal amount of the Outstanding Securities may declare
the Default Amount of all the Securities to be due and payable immediately, by a
notice in writing to the Company (and to the Trustee if given by Holders), and
upon any such declaration such Default Amount and any accrued interest, together
with all other amounts due under this Indenture, shall become immediately due
and payable. If an Event of Default specified in Section 501(8) or (9) with
respect to the Company occurs, the Default Amount of and any accrued interest on
the Securities then Outstanding, together with all other amounts due under this
Indenture, shall ipso facto become immediately due and payable without any
declaration or other Act on the part of the Trustee or any Holder.

                  The "Default Amount" in respect of any particular Security as
of any particular date of acceleration shall equal the principal amount of the
Security plus accrued and unpaid interest to such date.

                  At any time after such a declaration of acceleration has been
made and before a judgment or decree for payment of the money due based on
acceleration has been obtained by the Trustee as hereinafter in this Article
provided, the Holders of a majority in aggregate principal amount of the
Outstanding Securities, by written notice to the Company and the Trustee, may
rescind and annul such declaration and its consequences if:

                  (1)  the Company has paid or deposited with the
         Trustee a sum sufficient to pay

                           (A) all overdue interest on all Securities,

                           (B) the principal of (and premium, if any, on) any
                  Securities which have become due otherwise than by such
                  declaration of acceleration (including any Securities
                  required to have been purchased on the Purchase Date pursuant
                  to an Offer to Purchase made by the Company) and interest
                  thereon at the rate borne by the Securities,

                           (C) to the extent that payment of such interest is
                  lawful, interest 


                                      -55-


                  upon overdue interest at the applicable rate borne by the
                  Securities, and

                           (D) all sums paid or advanced by the Trustee
                  hereunder and the reasonable compensation, expenses,
                  disbursements and advances of the Trustee, its agents and
                  counsel;

         and

                  (2) all Events of Default, other than the non-payment of the
         principal of Securities which have become due solely by such
         declaration of acceleration, have been cured or waived as provided in
         Section 513.

No such rescission shall affect any subsequent default or impair any right
consequent thereon.


SECTION 503. COLLECTION OF INDEBTEDNESS AND SUITS FOR ENFORCEMENT BY TRUSTEE.

                  The Company covenants that if

                  (1) default is made in the payment of any interest on any
         Security when such interest becomes due and payable and such default
         continues for a period of 30 days, or

                  (2) default is made in the payment of the principal of (or
         premium, if any, on) any Security at the Maturity thereof or, with
         respect to any Security required to have been purchased pursuant to an
         Offer to Purchase made by the Company, at the Purchase Date thereof,

the Company will, upon demand of the Trustee, pay to it, for the benefit of the
Holders of such Securities, the whole amount then due and payable on such
Securities for principal (and premium, if any) and interest, and, to the extent
that payment of such interest shall be legally enforceable, interest on any
overdue principal (and premium, if any) and on any overdue interest, at the rate
provided by the Securities, and, in addition thereto, such further amount as
shall be sufficient to cover the costs and expenses incurred by the Trustee
under this Indenture, including the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel.

                  If the Company fails to pay such amounts forthwith upon such
demand, the Trustee, in its own name and as 


                                      -56-


trustee of an express trust, may institute a judicial proceeding for the
collection of the sums so due and unpaid, may prosecute such proceeding to
judgment or final decree, and may enforce the same against the Company or any
other obligor upon the Securities and collect the moneys adjudged or decreed to
be payable in the manner provided by law out of the property of the Company or
any other obligor upon the Securities, wherever situated.

                  If an Event of Default occurs and is continuing, the Trustee
may in its discretion proceed to protect and enforce its rights and the rights
of the Holders by such appropriate judicial proceedings as the Trustee shall
deem most effective to protect and enforce any such rights, whether for the
specific enforcement of any covenant or agreement in this Indenture or in aid of
the exercise of any power granted herein, or to enforce any other proper remedy.


SECTION 504.  TRUSTEE MAY FILE PROOFS OF CLAIM.

                  In case of any judicial proceeding relative to the Company (or
any other obligor upon the Securities), its property or its creditors, the
Trustee shall be entitled and empowered, by intervention in such proceeding or
otherwise, to take any and all actions authorized under the Trust Indenture Act
in order to have claims of the Holders and the Trustee allowed in any such
proceeding. In particular, the Trustee shall be authorized to collect and
receive any moneys, securities or other property payable or deliverable upon the
exchange of the Securities or upon any such claims and to distribute the same;
and any custodian, receiver, assignee, trustee, liquidator, sequestrator or
other similar official in any such judicial proceeding is hereby authorized by
each Holder to make such payments to the Trustee and, in the event that the
Trustee shall consent to the making of such payments directly to the Holders, to
pay to the Trustee any amount due it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any other
amounts due the Trustee under Section 607.

                  No provision of this Indenture shall be deemed to authorize
the Trustee to authorize or consent to or accept or adopt on behalf of any
Holder any plan of reorganization, arrangement, adjustment or composition
affecting the Securi ties or the rights of any Holder thereof or to authorize
the Trustee to vote in respect of the claim of any Holder in any such
proceeding; PROVIDED, HOWEVER, that the Trustee may, on behalf of the Holders,
vote for the election of a trustee in 


                                      -57-


bankruptcy or similar official and be a member of a creditors or other similar
committee.

SECTION 505. TRUSTEE MAY ENFORCE CLAIMS WITHOUT POSSESSION OF SECURITIES.

                  All rights of action and claims under this Indenture or the
Securities may be prosecuted and enforced by the Trustee without the possession
of any of the Securities or the production thereof in any proceeding relating
thereto, and any such proceeding instituted by the Trustee shall be brought in
its own name as trustee of an express trust, and any recovery of judgment shall,
after provision for the payment of the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, be for the
ratable benefit of the Holders of the Securities in respect of which such
judgment has been recovered.


SECTION 506.  APPLICATION OF MONEY COLLECTED.

                  Any money collected by the Trustee pursuant to this Article
shall be applied in the following order, at the date or dates fixed by the
Trustee and, in case of the distribution of such money on account of principal
(or premium, if any) or interest, upon presentation of the Securities and the
notation thereon of the payment if only partially paid and upon surrender
thereof if fully paid:

                  FIRST:  To the payment of all amounts due the
         Trustee under Section 607; and

                  SECOND: To the payment of the amounts then due and unpaid for
         principal of (and premium, if any) and interest on the Securities in
         respect of which or for the benefit of which such money has been
         collected, ratably, without preference or priority of any kind,
         according to the amounts due and payable on such Securities for
         principal (and premium, if any) and interest, respectively.

The Trustee, upon prior written notice to the Company, may fix a record date and
payment date for any payment to the Holders pursuant to this Section 506.


SECTION 507.  LIMITATION ON SUITS.

                  No Holder of any Security shall have any right to institute
any proceeding, judicial or otherwise, with 


                                      -58-



respect to this Indenture, or for the appointment of a receiver or trustee, or
for any other remedy hereunder, unless

                  (1) such Holder has previously given written notice to the
         Trustee of a continuing Event of Default;

                  (2) the Holders of at least 25% in aggregate principal amount
         of the Outstanding Securities shall have made written request to the
         Trustee to institute proceedings in respect of such Event of Default in
         its own name as Trustee hereunder;

                  (3) such Holder or Holders have offered and, if requested,
         provided to the Trustee reasonable indemnity against the costs,
         expenses and liabilities to be incurred in compliance with such
         request;

                  (4) the Trustee for 60 days after its receipt of such notice,
         request and offer and, if requested, provision of indemnity has failed
         to institute any such proceeding; and

                  (5) no direction inconsistent with such written request has
         been given to the Trustee during such 60-day period by the Holders of a
         majority in principal amount of the Outstanding Securities;

it being understood and intended that no one or more Holders shall have any
right in any manner whatever by virtue of, or by availing of, any provision of
this Indenture to affect, disturb or prejudice the rights of any other Holders,
or to obtain or to seek to obtain priority or preference over any other Holders
or to enforce any right under this Indenture, except in the manner herein
provided and for the equal and ratable benefit of all the Holders.


SECTION 508. UNCONDITIONAL RIGHT OF HOLDERS TO RECEIVE PRINCIPAL, PREMIUM AND
             INTEREST.

                  Notwithstanding any other provision in this Indenture, the
Holder of any Security shall have the right, which is absolute and
unconditional, to receive payment of the principal of (and premium, if any) and
(subject to Section 307) interest on such Security on the respective Stated
Maturities expressed in such Security (or, in the case of redemption, on the
Redemption Date or, in the case of an Offer to Purchase made by the Company and
required to be accepted as to such Security, on the Purchase Date) and to


                                      -59-



institute suit for the enforcement of any such payment, and such rights shall
not be impaired without the consent of such Holder.

SECTION 509.  RESTORATION OF RIGHTS AND REMEDIES.

                  If the Trustee or any Holder has instituted any proceeding to
enforce any right or remedy under this Indenture and such proceeding has been
discontinued or abandoned for any reason, or has been determined adversely to
the Trustee or to such Holder, then and in every such case, subject to any
determination in such proceeding, the Company, the Trustee and the Holders shall
be restored severally and respectively to their former positions hereunder and
thereafter all rights and remedies of the Trustee and the Holders shall
continue as though no such proceeding had been instituted.


SECTION 510.  RIGHTS AND REMEDIES CUMULATIVE.

                  Except as otherwise provided with respect to the replacement
or payment of mutilated, destroyed, lost or stolen Securities in the last
paragraph of Section 306, no right or remedy herein conferred upon or reserved
to the Trustee or to the Holders is intended to be exclusive of any other right
or remedy, and every right and remedy shall, to the extent permitted by law, be
cumulative and in addition to every other right and remedy given hereunder or
now or hereafter existing at law or in equity or otherwise. The assertion or
employment of any right or remedy hereunder, or otherwise, shall not prevent the
concurrent assertion or employment of any other appropriate right or remedy.


SECTION 511.  DELAY OR OMISSION NOT WAIVER.

                  No delay or omission of the Trustee or of any Holder of any
Security to exercise any right or remedy accruing upon any Event of Default
shall impair any such right or remedy or constitute a waiver of any such Event
of Default or an acquiescence therein. Every right and remedy given by this
Article or by law to the Trustee or to the Holders may be exercised from time to
time, and as often as may be deemed expedient, by the Trustee or by the Holders,
as the case may be.


                                      -60-


SECTION 512.  CONTROL BY HOLDERS.

                  The Holders of a majority in aggregate principal amount of the
Outstanding Securities shall have the right to direct the time, method and place
of conducting any proceeding for any remedy available to the Trustee or
exercising any trust or power conferred on the Trustee, PROVIDED that

                  (1) such direction shall not be in conflict with any rule of
         law or with this Indenture or expose the Trustee to personal liability
         (as determined in the sole discretion of the Trustee), and

                  (2) the Trustee may take any other action deemed proper by the
         Trustee which is not inconsistent with such direction.

The Trustee may refuse, however, to follow any direction that the Trustee, in
its sole discretion, determines may be unduly prejudicial to the rights of
another Holder or that may subject the Trustee to any liability or expense if
the Trustee determines, in its sole discretion, that it lacks indemnification
against such loss or expense.


SECTION 513.  WAIVER OF PAST DEFAULTS.

                  The Holders of not less than a majority in aggregate principal
amount of the Outstanding Securities may on behalf of the Holders of all the
Securities by written notice to the Trustee waive any past default hereunder and
its consequences, except a default

                  (1) in the payment of the principal of (or premium, if any) or
         interest on any Security (including any Security which is required to
         have been purchased pursuant to an Offer to Purchase which has been
         made by the Company), or

                  (2) in respect of a covenant or provision hereof which under
         Article Nine cannot be modified or amended without the consent of the
         Holder of each Outstanding Security affected or

                  (3) arising from failure to purchase any Security tendered
         pursuant to Sections 1013 and 1016.

                  Upon any such waiver, such default shall cease to exist, and
any Event of Default arising therefrom shall be deemed to have been cured, for
every purpose of this Indenture; 


                                      -61-


but no such waiver shall extend to any subsequent or other default or impair any
right consequent thereon.

SECTION 514.  UNDERTAKING FOR COSTS.

                  In any suit for the enforcement of any right or remedy under
this Indenture, or in any suit against the Trustee for any action taken or
omitted by it as Trustee, a court may require any party litigant in such suit to
file an undertaking to pay the costs of such suit, and may assess costs against
any such party litigant, in the manner and to the extent provided in the Trust
Indenture Act; PROVIDED that neither this Section nor the Trust Indenture Act
shall be deemed to authorize any court to require such an undertaking or to make
such an assessment in any suit instituted by the Company.


SECTION 515.  WAIVER OF STAY OR EXTENSION LAWS.

                  The Company covenants (to the extent that it may lawfully do
so) that it will not at any time insist upon, or plead, or in any manner
whatsoever claim or take the benefit or advantage of, any stay or extension law
wherever enacted, now or at any time hereafter in force, which may affect the
covenants or the performance of this Indenture; and the Company (to the extent
that it may lawfully do so) hereby expressly waives all benefit or advantage of
any such law and covenant that they will not hinder, delay or impede the
execution of any power herein granted to the Trustee, but will suffer and permit
the execution of every such power as though no such law had been enacted.


                                   ARTICLE SIX

                                   The Trustee

SECTION 601.  CERTAIN DUTIES AND RESPONSIBILITIES.

                  The duties and responsibilities of the Trustee shall be as
provided by the Trust Indenture Act. Notwithstanding the foregoing, no
provision of this Indenture shall require the Trustee to expend or risk its own
funds or otherwise incur any financial liability in the performance of any of
its duties hereunder, or in the exercise of any of its rights or powers, if it
shall have reasonable grounds for believing that repayment of such funds or
adequate indemnity against such risk or liability is not reasonably assured to
it. Whether or not therein expressly so provided



                                      -62-



every provision of this Indenture relating to the conduct or affecting the
liability of or affording protec tion to the Trustee shall be subject to the
provisions of this Section.


SECTION 602.  NOTICE OF DEFAULTS.

                  The Trustee shall give the Holders notice of any Default
hereunder as and to the extent provided by the Trust Indenture Act, unless such
Default has been cured or waived; PROVIDED, HOWEVER, that in the case of any
Default of the character specified in Section 501(5), no such notice to Holders
shall be given until at least 30 days after the occurrence thereof.


SECTION 603.  CERTAIN RIGHTS OF TRUSTEE.

                  Subject to the provisions of Section 601:

                  (a) the Trustee may rely and shall be protected in acting or
         refraining from acting upon any resolution, certificate, statement,
         instrument, opinion, report, notice, request, direction, consent,
         order, bond, debenture, note, other evidence of indebtedness or other
         paper or document believed by it to be genuine and to have been signed
         or presented by the proper party or parties;

                  (b) any request or direction of the Company mentioned herein
         shall be sufficiently evidenced by a Company Request or a Company Order
         and any resolution of the Board of Directors may be sufficiently
         evidenced by a Board Resolution;

                  (c) whenever in the administration of this Indenture the
         Trustee shall deem it desirable that a matter be proved or established
         prior to taking, suffering or omitting any action hereunder, the
         Trustee (unless other evidence be herein specifically prescribed) may,
         in the absence of bad faith on its part, rely upon an Officers'
         Certificate or an Opinion of Counsel;

                  (d) the Trustee may consult with counsel and the written
         advice of such counsel or any Opinion of Counsel shall be full and
         complete authorization and protection in respect of any action taken,
         suffered or omitted by it hereunder in good faith and in reliance
         thereon;


                                      -63-


                  (e) the Trustee shall be under no obligation to exercise any
         of the rights or powers vested in it by this Indenture at the request
         or direction of any of the Holders pursuant to this Indenture, unless
         such Holders shall have offered to the Trustee reasonable security or
         indemnity against the costs, expenses and liabilities which might be
         incurred by it in compliance with such request or direction reasonably
         satisfactory to the Trustee;

                  (f) the Trustee shall not be bound to make any investigation
         into the facts or matters stated in any resolution, certificate,
         statement, instrument, opinion, report, notice, request, direction,
         consent, order, bond, debenture, note, other evidence of indebtedness
         or other paper or document, but the Trustee, in its discretion, may
         make such further inquiry or investigation into such facts or matters
         as it may see fit, and, if the Trustee shall determine to make such
         further inquiry or investigation, it shall be entitled to examine the
         books, records and premises of the Company, personally or by agent or
         attorney;

                  (g) the Trustee may execute any of the trusts or powers
         hereunder or perform any duties hereunder either directly or by or
         through agents or attorneys and the Trustee shall not be responsible
         for any misconduct or negligence on the part of any agent or attorney
         appointed with due care by it hereunder; and

                  (h) the Trustee shall not be liable for any action taken,
         suffered or omitted by it in good faith which the Trustee reasonably
         believed to have been authorized or within its rights or powers.


SECTION 604.     NOT RESPONSIBLE FOR RECITALS
                 OR ISSUANCE OF SECURITIES.   

                  The recitals contained herein and in the Securities, except
the Trustee's certificates of authentication, shall be taken as the statements
of the Company, and the Trustee assumes no responsibility for their correctness.
The Trustee makes no representations as to the validity or sufficiency of this
Indenture or the Securities. The Trustee shall not be accountable for the use or
application by the Company of Securities or the proceeds thereof.


                                      -64-


SECTION 605.  MAY HOLD SECURITIES.

                  The Trustee, any Paying Agent, any Security Registrar (if
other than the Trustee) or any other agent of the Company, in its individual or
any other capacity, may become the owner or pledgee of Securities and, subject
to Sections 608 and 613, may otherwise deal with the Company with the same
rights it would have if it were not Trustee, Paying Agent, Security Registrar or
such other agent.


SECTION 606.  MONEY HELD IN TRUST.

                  Money held by the Trustee in trust hereunder need not be
segregated from other funds except to the extent required by law. The Trustee
shall be under no liability for interest on any money received by it hereunder
except as otherwise agreed with the Company.


SECTION 607.  COMPENSATION AND REIMBURSEMENT.

                  The Company agrees

                  (1) to pay to the Trustee from time to time reasonable
         compensation for all services rendered by it hereunder (which
         compensation shall not be limited by any provision of law in regard to
         the compensation of a trustee of an express trust);

                  (2) except as otherwise expressly provided herein, to
         reimburse the Trustee upon its request for all reasonable expenses,
         disbursements and advances incurred or made by the Trustee in
         accordance with any provision of this Indenture (including the
         reasonable compensation and the expenses and disbursements of its
         agents and counsel), except any such expense, disbursement or advance
         as may be attributable to its negligence or bad faith; and

                  (3) to indemnify the Trustee for, and to hold it harmless
         against, any loss, liability or expense (including the reasonable
         compensation, expenses and disbursements of its agents, accountants,
         experts and counsel) incurred without negligence or bad faith on its
         part, arising out of or in connection with the acceptance or
         administration of this trust, including the costs and expenses of
         enforcing this Indenture against the Company (including, without
         limitation, this Section 607) and of defending itself against any
         claim (whether asserted by any Holder or the Company) 



                                      -65-


         or liability in connection with the exercise or performance of any of
         its powers or duties hereunder. The provisions of this Section 607
         shall survive any termination of this Indenture and the resignation or
         removal of the Trustee.

                  As security for the performance of the obligations of the
Company under this Section 607, the Trustee shall have a lien prior to the
Securities upon all property and funds held or collected by the Trustee, except
funds held in trust for the payment of principal of (and premium, if any) or
interest on particular Securities. The Trustee's right to receive payment of any
amounts due under this Section 607 shall not be subordinate to any other
liability or indebtedness of the Company (even though the Securities may be so
subordinated).

                  When the Trustee incurs expenses or renders services after an
Event of Default specified in Section 501(8) or (9) occurs, the expenses and the
compensation for such services are intended to constitute expenses of
administration under Title 11, U.S. Code, or any similar Federal state or
foreign law for the relief of debtors.


SECTION 608.  DISQUALIFICATION; CONFLICTING INTERESTS.

                  If the Trustee has or shall acquire a conflicting interest
within the meaning of the Trust Indenture Act, the Trustee shall either
eliminate such interest or resign, to the extent and in the manner provided by,
and subject to the provisions of, the Trust Indenture Act and this Indenture.


SECTION 609.  CORPORATE TRUSTEE REQUIRED; ELIGIBILITY.

                  There shall at all times be a Trustee hereunder which shall be
a Person that is eligible pursuant to the Trust Indenture Act to act as such and
has a combined capital and surplus of at least $50,000,000 and its Corporate
Trust Office in the Borough of Manhattan, The City of New York, New York. If
such Person publishes reports of condition at least annually, pursuant to law
or to the requirements of a Federal, State, Territorial or District of Columbia
supervising or examining authority, then for the purposes of this Section, the
combined capital and surplus of such Person shall be deemed to be its combined
capital and surplus as set forth in its most recent report of condition so
published. If at any time the Trustee shall cease to be eligible in accordance
with the provisions of



                                      -66-


this Section, it shall resign immediately in the manner and with the effect
hereinafter specified in this Article.


SECTION 610.      RESIGNATION AND REMOVAL; APPOINTMENT
                  OF SUCCESSOR.                        

                  (a) No resignation or removal of the Trustee and no
appointment of a successor Trustee pursuant to this Article shall become
effective until the acceptance of appointment by the successor Trustee under
Section 611, at which time the retiring Trustee shall be fully discharged from
its obligations hereunder.

                  (b) The Trustee may resign at any time by giving written
notice thereof to the Company. If an instrument of acceptance by a successor
Trustee shall not have been delivered to the Trustee within 30 days after the
giving of such notice of resignation, the resigning Trustee may petition any
court of competent jurisdiction for the appointment of a successor Trustee.

                  (c) The Trustee may be removed at any time by Act of the
Holders of a majority in principal amount of the Outstanding Securities,
delivered to the Trustee and to the Company.

                  (d) If at any time:

                  (1) the Trustee shall fail to comply with Section 608 after
         written request therefor by the Company or by any Holder who has been a
         bona fide Holder of a Security for at least six months, or

                  (2) the Trustee shall cease to be eligible under Section 609
         and shall fail to resign after written request therefor by the Company
         or by any such Holder, or

                  (3) the Trustee shall become incapable of acting or shall be
         adjudged a bankrupt or insolvent or a receiver of the Trustee or of its
         property shall be appointed or any public officer shall take charge or
         control of the Trustee or of its property or affairs for the purpose of
         rehabilitation, conservation or liquidation,

then, in any such case, (i) the Company, by Board Resolution, may remove the
Trustee, or (ii) subject to Section 514, any Holder who has been a bona fide
Holder of a Security for at least six months may, on behalf of himself



                                      -67-


and all others similarly situated, petition any court of competent jurisdiction
for the removal of the Trustee and the appointment of a successor Trustee.

                  (e) If the Trustee shall resign, be removed or become
incapable of acting, or if a vacancy shall occur in the office of Trustee for
any cause, the Company, by Board Resolution, shall promptly appoint a successor
Trustee. If, within one year after such resignation, removal or incapability,
or the occurrence of such vacancy, a successor Trustee shall be appointed by Act
of the Holders of a majority in principal amount of the Outstanding Securities
delivered to the Company and the retiring Trustee, the successor Trustee so
appointed shall, forthwith upon its acceptance of such appointment, become the
successor Trustee and supersede the successor Trustee appointed by the Company.
If no successor Trustee shall have been so appointed by the Company or the
Holders and accepted appointment in the manner hereinafter provided, any Holder
who has been a bona fide Holder of a Security for at least six months may, on
behalf of himself and all others similarly situated, petition any court of
competent jurisdiction for the appointment of a successor Trustee.

                  (f) The Company shall give notice of each resig nation and
each removal of the Trustee and each appointment of a successor Trustee to all
Holders in the manner provided in Section 106. Each notice shall include the
name of the successor Trustee and the address of its Corporate Trust Office.


SECTION 611.  ACCEPTANCE OF APPOINTMENT BY SUCCESSOR.

                  Every successor Trustee appointed hereunder shall execute,
acknowledge and deliver to the Company and to the retiring Trustee an instrument
accepting such appointment, and thereupon the resignation or removal of the
retiring Trustee shall become effective and such successor Trustee, without any
further act, deed or conveyance, shall become vested with all the rights,
powers, trusts and duties of the retiring Trustee; but, on request of the
Company or the successor Trustee under Section 607, execute and deliver an
instrument transferring to such successor Trustee all the rights, powers and
trusts of the retiring Trustee and shall duly assign, transfer and deliver to
such successor Trustee all property and money held by such retiring Trustee
hereunder. Upon request of any such successor Trustee, the Company shall execute
any and all instruments for more fully and certainly vesting in and confirming
to such successor Trustee all such rights, powers and trusts.



                                      -68-


                  No successor Trustee shall accept its appointment unless at
the time of such acceptance such successor Trustee shall be qualified and
eligible under this Article.


SECTION 612.      MERGER, CONVERSION, CONSOLIDATION
                  OR SUCCESSION TO BUSINESS.        

                  Any corporation into which the Trustee may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, conversion or consolidation to which the Trustee shall be a
party, or any corporation succeeding to all or substantially all the corporate
trust business of the Trustee, shall be the successor of the Trustee hereunder,
PROVIDED that such corporation shall be otherwise qualified and eligible under
this Article, without the execution or filing of any paper or any further act on
the part of any of the parties hereto. In case any Securities shall have been
authenticated, but not delivered, by the Trustee then in office, any successor
by merger, conversion or consolidation to such authenticating Trustee may adopt
such authentication and deliver the Securities so authenticated with the same
effect as if such successor Trustee had itself authenticated such Securities.


SECTION 613.      PREFERENTIAL COLLECTION
                  OF CLAIMS AGAINST THE COMPANY.

                  If and when the Trustee shall be or become a creditor of the
Company (or any other obligor upon the Securities), the Trustee shall be subject
to the provisions of the Trust Indenture Act regarding the collection of claims
against the Company (or any such other obligor).


SECTION 614.      APPOINTMENT OF AUTHENTICATING AGENT.

                  The Trustee may appoint an Authenticating Agent or Agents 
with respect to the Securities which shall be authorized to act on behalf of 
the Trustee to authenticate Securities issued upon original issue and upon 
exchange, registration of transfer or partial redemption thereof or pursuant 
to Section 306, and Securities so authenticated shall be entitled to the 
benefits of this Indenture and shall be valid and obligatory for all purposes 
as if authenticated by the Trustee hereunder. Wherever reference is made in 
this Indenture to the authentication and delivery of Securities by the 
Trustee or the Trustee's certificate of authentication, such reference shall 
be deemed to include

                                      -69-


authentication and delivery on behalf of the Trustee by an Authenticating Agent
and a certificate of authentication executed on behalf of the Trustee by an
Authenticating Agent. Each Authenticating Agent shall be acceptable to the
Company and shall at all times be a corporation organized and doing business
under the laws of the United States of America, any State thereof or the
District of Columbia, authorized under such laws to act as Authenticating Agent,
having a combined capital and surplus of not less than $50,000,000 and subject
to supervision or examination by Federal or State authority. If such
Authenticating Agent publishes reports of condition at least annually, pursuant
to law or to the requirements of said supervising or examining authority, then
for the purposes of this Section, the combined capital and surplus of such
Authenticating Agent shall be deemed to be its combined capital and surplus as
set forth in its most recent report of condition so published. If at any time an
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, such Authenticating Agent shall resign immediately
in the manner and with the effect specified in this Section.

                  Any corporation into which an Authenticating Agent may be
merged or converted or with which it may be consolidated, or any corporation
resulting from any merger, conversion or consolidation to which such
Authenticating Agent shall be a party, or any corporation succeeding to the
corporate agency or corporate trust business of an Authenticating Agent, shall
continue to be an Authenticating Agent, provided such corporation shall be
otherwise eligible under this Section, without the execution or filing of any
paper or any further act on the part of the Trustee or the Authenticating
Agent.

                  An Authenticating Agent may resign at any time by giving 
written notice thereof to the Trustee and to the Company. The Trustee may at 
any time terminate the agency of an Authenticating Agent by giving written 
notice thereof to such Authenticating Agent and to the Company. Upon 
receiving such a notice of resignation or upon such a termination, or in case 
at any time such Authenticating Agent shall cease to be eligible in 
accordance with the provisions of this Section, the Trustee may appoint a 
successor Authenticating Agent which shall be acceptable to the Company and 
shall give notice of such appointment in the manner provided in Section 106 
to all Holders of Securities. Any successor Authenticating Agent upon 
acceptance of its appointment hereunder shall become vested with all the 
rights, powers and duties of its predecessor hereunder, with like effect as 
if originally named as an Authenticating 

                                      -70-


Agent. No successor Authenticating Agent shall be appointed unless eligible
under the provisions of this Section.

                  The Trustee agrees to pay to each Authenticating Agent from
time to time reasonable compensation for its services under this Section, and
the Trustee shall be entitled to be reimbursed for such payments, subject to the
provisions of Section 607.

                  If an appointment is made pursuant to this Section, the
Securities may have endorsed thereon, in lieu of the Trustee's certificate of
authentication, an alternative certificate of authentication in the following
form:

                  This is one of the Securities referred to in the
within-mentioned Indenture.


                                        United States Trust Company of New York,
                                                                      AS TRUSTEE


                                       By......................................,
                                                         AS AUTHENTICATING AGENT

                                       By.......................................
                                                            AUTHORIZED SIGNATORY



                                  ARTICLE SEVEN

              Holders' Lists and Reports by Trustee and the Company

SECTION 701.      COMPANY TO FURNISH TRUSTEE
                  NAMES AND ADDRESSES OF HOLDERS.
 
                  The Company will furnish or cause to be furnished
to the Trustee

                  (a) semi-annually, not more than 15 days after each Regular
         Record Date, a list, in such form as the Trustee may reasonably
         require, of the names and ad dresses of the Holders as of such Regular
         Record Date, and

                  (b) at such other times as the Trustee may request in writing,
         within 30 days after the receipt by the Company of any such request, a
         list of similar form 



                                      -71-


         and content as of a date not more than 15 days prior to the time such
         list is furnished;

EXCLUDING from any such list names and addresses received by the Trustee in its
capacity as Security Registrar.


SECTION 702.      PRESERVATION OF INFORMATION;
                  COMMUNICATIONS TO HOLDERS.   

                  (a) The Trustee shall preserve, in as current a form as is
reasonably practicable, the names and addresses of Holders contained in the most
recent list furnished to the Trustee as provided in Section 701 and the names
and addresses of Holders received by the Trustee in its capacity as Security
Registrar. The Trustee may destroy any list furnished to it as provided in
Section 701 upon receipt of a new list so furnished.

                  (b) The rights of Holders to communicate with other Holders
with respect to their rights under this Indenture or under the Securities, and
the corresponding rights and duties of the Trustee, shall be as provided by the
Trust Indenture Act.

                  (c) Every Holder of Securities, by receiving and holding the
same, agrees with the Company and the Trustee that none of the Company, the
Trustee or any agent of any of them shall be held accountable by reason of any
disclosure of information as to names and addresses of Holders made pursuant to
the Trust Indenture Act.


SECTION 703.  REPORTS BY TRUSTEE.

                  (a) The Trustee shall transmit to Holders such reports
concerning the Trustee and its actions under this Indenture as may be required
pursuant to the Trust Indenture Act at the times and in the manner provided
pursuant thereto.

                  (b) A copy of each such report shall, at the time of such
transmission to Holders, be filed by the Trustee with each stock exchange upon
which the Securities are listed, with the Commission and with the Company. The
Company will notify the Trustee when the Securities are listed on any stock
exchange.


                                      -72-


SECTION 704.  REPORTS BY COMPANY.

                  The Company shall file with the Trustee and the Commission,
and transmit to Holders, such information, documents and other reports, and
such summaries thereof, as may be required pursuant to the Trust Indenture Act
at the times and in the manner provided pursuant to such Act and in the manner
set forth in Section 1017; PROVIDED that any such information, documents or
reports required to be filed with the Commission pursuant to Section 13 or 15(d)
of the Exchange Act ("SEC Reports") shall be filed with the Trustee within 15
days after the same is so required to be filed with the Commission. In the event
the Company shall cease to be required to file SEC Reports pursuant to the
Exchange Act, the Company will nonetheless continue to file such reports with
the Commission (unless the Commission will not accept such a filing) and the
Trustee and to furnish copies of such SEC Reports to the Holders of Securities
at the time the Company is required to file such reports with the Trustee and
will make such information available to investors who request it in writing.


                                  ARTICLE EIGHT

                           Merger, Consolidation, Etc.

SECTION 801.    MERGERS, CONSOLIDATIONS AND CERTAIN SALES OF ASSETS.

                  (a) The Company may not, in a single transaction or a series
of related transactions, (i) consolidate with or merge into any other Person or
permit any other Person to consolidate with or merge into the Company (other
than a consolidation or merger of a Wholly-Owned Restricted Subsidiary organized
under the laws of a State of the United States into the Company), or (ii)
directly or indirectly, transfer, sell, lease or otherwise dispose of all or
substantially all of its assets (determined on a consolidated basis for the
Company and its Restricted Subsidiaries taken as a whole and provided that the
creation of a Lien on or in any of its assets shall not in and of itself
constitute the transfer, sale, lease or disposition of the assets subject to the
Lien), unless: (1) in a transaction in which the Company does not survive or in
which the Company sells, leases or otherwise disposes of all or substantially
all of its assets to any other Person, the successor entity to the Company shall
be a corporation organized under the laws of the United States of America or
any State thereof or the District of Columbia and shall expressly assume, by a
supplemental indenture executed and 



                                      -73-


delivered to the Trustee in form satisfactory to the Trustee, all of the
Company's obligations under this Indenture; (2) immediately after giving pro
forma effect to such transaction as if such transaction had occurred at the
beginning of the last full fiscal quarter immediately prior to the consummation
of such transaction with the appropriate adjustments with respect to the
transaction being included in such pro forma calculation and treating any Debt
which becomes an obligation of the Company or a Subsidiary as a result of such
transaction as having been Incurred by the Company or such Subsidiary at the
time of the transaction, no Default or Event of Default shall have occurred and
be continuing; (3) immediately after giving effect to such transaction, the
Consolidated Net Worth of the Company (or other successor entity to the Company)
is equal to or greater than that of the Company immediately prior to the
transaction; (4) if, as a result of any such transaction, property or assets of
the Company would become subject to a Lien prohibited by the provisions of
Section 1011, the Company or the successor entity to the Company shall have
secured the Securities as required by Section 1011;(5) the Company has delivered
to the Trustee an Officer's Certificate and an Opinion of Counsel, each in form
and substance satisfactory to the Trustee stating that such consolidation,
merger, conveyance, transfer, lease or acquisition and, if a supplemental
indenture is required in connection with such transaction, such supplemental
indenture, complies with this Article and that all conditions precedent herein
provided for relating to such transaction have been complied with, and, with
respect to such Officer's Certificate, setting forth the manner of determination
of the Consolidated Net Worth in accordance with Clause (3) of Section 801, of
the Company or, if applicable, of the Successor Company as required pursuant to
the foregoing.

                  (b) In the event of any transaction (other than a lease)
described in and complying with the immediately preceding paragraph in which the
Company is not the surviving Person and the surviving Person assumes all the
obligations of the Company under the Securities and this Indenture pursuant to a
supplemental indenture, such surviving Person shall succeed to, and be
substituted for, and may exercise every right and power of, the Company, and the
Company will be discharged from its obligations under this Indenture and the
Securities; PROVIDED that solely for the purpose of calculating amounts under
Section 1009(3), any such surviving Person shall only be deemed to have
succeeded to and be substituted for the Company with respect to the period
subsequent to the effective time of such transaction, and the Company (before
giving effect to such 



                                      -74-


transaction) shall be deemed to be the "Company" for such purposes for all prior
periods.


SECTION 802.  SUCCESSOR SUBSTITUTED.

                  Upon any consolidation of the Company with, or merger of the
Company with or into, any other Person or any conveyance, transfer or lease of
the properties and assets of the Company substantially as an entirety in
accordance with Section 801, the successor Person formed by such consolidation
or into which the Company is merged or to which such conveyance, transfer or
lease is made shall succeed to, and be substituted for, and may exercise every
right and power of, the Company under this Indenture with the same effect as if
such successor Person had been named as the Company herein, and thereafter,
except in the case of a lease, the predecessor Person shall be relieved of all
obligations and covenants under this Indenture and the Securities.


                                  ARTICLE NINE

                             Supplemental Indentures

SECTION 901.      SUPPLEMENTAL INDENTURES
                  WITHOUT CONSENT OF HOLDERS 

                  Without the consent of any Holders, the Company, when
authorized by Board Resolution, and the Trustee, at any time and from time to
time, may enter into one or more indentures supplemental hereto, in form
satisfactory to the Trustee, for any of the following purposes:

                  (1) to evidence the succession of another Person to the
         Company and the assumption by any such successor of the covenants of
         the Company herein and in the Securities; or

                  (2) to add to the covenants of the Company for the benefit of
         the Holders, or to surrender any right or power herein conferred upon
         the Company; or

                  (3) to secure the Securities pursuant to the requirements of
         Section 1011 or otherwise; or

                  (4) to modify, eliminate or add to the provisions of this
         Indenture to such extent as shall be necessary to comply with any
         requirement of the Commission in 



                                      -75-


         order to maintain the qualification of this Indenture under the Trust
         Indenture Act;

                  (5) to cure any ambiguity, to correct or supplement any
         provision herein which may be inconsistent with any other provision
         herein, or to make any other provisions with respect to matters or
         questions arising under this Indenture which shall not be inconsistent
         with the provisions of this Indenture, PROVIDED that such action
         pursuant to this Clause (5) shall not adversely affect the legal rights
         of the Holders; or

                  (6) to provide for uncertificated Securities in addition to or
         in place of certificated Securities.


SECTION 902.      SUPPLEMENTAL INDENTURES
                  WITH CONSENT OF HOLDERS. 

                  With the consent of the Holders of not less than a majority in
aggregate principal amount of the Outstanding Securities, by Act of said Holders
delivered to the Company and the Trustee, and consistent with Section 513, the
Company, when authorized by Board Resolution, and the Trustee may enter into an
indenture or indentures supplemental hereto for the purpose of adding any
provisions to or changing in any manner or eliminating any of the provisions of
this Indenture or of modifying in any manner the rights of the Holders under
this Indenture; PROVIDED, HOWEVER, that no such supplemental indenture shall,
without the consent of the Holder of each Outstanding Security affected thereby,

                  (1) change the Stated Maturity of the principal of, or any
         installment of interest on, any Security, or reduce the principal
         amount thereof or the rate of interest thereon or any premium payable
         thereon, or change the place of payment where, or the coin or currency
         in which, any Security or any premium or interest thereon is payable,
         or impair the right to institute suit for the enforcement of any such
         payment on or after the Stated Maturity thereof (or, in the case of
         redemption, on or after the Redemption Date) or, in the case of an
         Offer to Purchase which has been made, on or after the applicable
         Purchase Date, or

                  (2) reduce the percentage in principal amount of the
         Outstanding Securities, the consent of whose Holders is required for
         any such supplemental indenture, or the consent of whose Holders is
         required for any waiver (of compliance with certain provisions of 



                                      -76-


         this Indenture or certain defaults hereunder and their consequences)
         provided for in this Indenture, or

                  (3) modify any of the provisions of this Section, Section 513
         or Section 1019, except to increase any such percentage or to provide
         that certain other provisions of this Indenture cannot be modified or
         waived without the consent of the Holder of each Outstanding Security
         affected thereby, or

                  (4) following the mailing of an Offer with respect to an Offer
         to Purchase pursuant to Section 1013 or 1016 and until the Expiration
         Date of such Offer to Purchase, modify the provisions of this Indenture
         with respect to such Offer to Purchase in a manner materially adverse
         to such Holder.

                  It shall not be necessary for any Act of Holders under this
Section to approve the particular form of any proposed supplemental indenture,
but it shall be sufficient if such Act shall approve the substance thereof.


SECTION 903.  EXECUTION OF SUPPLEMENTAL INDENTURES.

                  In executing, or accepting the additional trusts created by,
any supplemental indenture permitted by this Article or the modifications
thereby of the trusts created by this Indenture, the Trustee shall be entitled
to receive, and (subject to Section 601) shall be fully protected in relying
upon, an Opinion of Counsel stating that the execution of such supplemental
indenture is authorized or permitted by this Indenture. The Trustee may, but
shall not be obligated to, enter into any such supplemental indenture which
affects the Trustee's own rights, duties or immunities under this Indenture or
otherwise.


SECTION 904.  EFFECT OF SUPPLEMENTAL INDENTURES.

                  Upon the execution of any supplemental indenture under this
Article, this Indenture shall be modified in accordance therewith, and such
supplemental indenture shall form a part of this Indenture for all purposes; and
every Holder of Securities theretofore or thereafter authenticated and delivered
hereunder shall be bound thereby.




                                      -77-


SECTION 905.  CONFORMITY WITH TRUST INDENTURE ACT.

                  Every supplemental indenture executed pursuant to this Article
shall conform to the requirements of the Trust Indenture Act.


SECTION 906.   REFERENCE IN SECURITIES
               TO SUPPLEMENTAL INDENTURES.

                  Securities authenticated and delivered after the execution of
any supplemental indenture pursuant to this Article may, and shall if required
by the Trustee, bear a notation in form approved by the Trustee as to any matter
provided for in such supplemental indenture. If the Company shall so determine,
new Securities so modified as to conform, in the opinion of the Trustee and the
Company, to any such supplemental indenture may be prepared and executed by the
Company and authenticated and delivered by the Trustee in exchange for
Outstanding Securities.


                                   ARTICLE TEN

                                    Covenants

SECTION 1001.  PAYMENT OF PRINCIPAL, PREMIUM AND
               INTEREST.                        

                  The Company will duly and punctually pay the principal of and
premium, if any, and interest on the Securities in accordance with the terms of
the Securities and this Indenture.


SECTION 1002.  MAINTENANCE OF OFFICE OR AGENCY.

                  The Company will maintain in the Borough of Manhattan, The
City of New York, New York, an office or agency where Securities may be
presented or surrendered for payment, where Securities may be surrendered for
registration of transfer or exchange and where notices and demands to or upon
the Company in respect of the Securities and this Indenture may be served. The
Company will give prompt written notice to the Trustee of the location, and any
change in the location, of such office or agency. If at any time the Company
shall fail to maintain any such required office or agency or shall fail to
furnish the Trustee with the address thereof, such presentations, surrenders,
notices and demands may be made or served at the Corporate Trust Office of the
Trustee, and the Company hereby appoints the



                                      -78-


Trustee as its agent to receive all such presentations, surrenders, notices and
demands.

                  The Company may also from time to time designate one or more
other offices or agencies (in or outside the Borough of Manhattan, The City of
New York, New York) where the Securities may be presented or surrendered for any
or all such purposes and may from time to time rescind such designations;
PROVIDED, HOWEVER, that no such designation or rescission shall in any manner
relieve the Company of its obligation to maintain an office or agency in the
Borough of Manhattan, The City of New York, New York for such purposes. The
Company will give prompt written notice to the Trustee of any such designation
or rescission and of any change in the location of any such other office or
agency.


SECTION 1003.     MONEY FOR SECURITY
                  PAYMENTS TO BE HELD IN TRUST.

                  If the Company shall at any time act as its own Paying Agent,
it will, on or before each due date of the principal of (and premium, if any) or
interest on any of the Securities, segregate and hold in trust for the benefit
of the Persons entitled thereto a sum sufficient to pay the principal (and
premium, if any) or interest so becoming due until such sums shall be paid to
such Persons or otherwise disposed of as herein provided and will promptly
notify the Trustee in writing of its action or failure so to act. As provided in
Section 504, upon any bankruptcy or reorganization proceeding relative to the
Company, the Trustee shall serve as the Paying Agent for the Securities.

                  Whenever the Company shall have one or more Paying Agents, it
will, prior to each due date of the principal of (and premium, if any) or
interest on any Securities, deposit with a Paying Agent a sum sufficient to pay
the principal (and premium, if any) or interest so becoming due, such sum to be
held in trust for the benefit of the Persons entitled to such principal, premium
or interest, and (unless such Paying Agent is the Trustee) the Company will
promptly notify the Trustee in writing of its action or failure so to act. As
provided in Section 504, upon any bankruptcy or reorganization proceeding
relative to the Company the Trustee shall serve as the Paying Agent for the
Securities.

                  The Company will cause each Paying Agent other than the
Trustee to execute and deliver to the Trustee an instrument in which such Paying
Agent shall agree with the Trustee, subject to the provisions of this Section,
that such Paying Agent will:



                                      -79-


                  (1) hold all sums held by it for the payment of the principal
         of (and premium, if any) or interest on Securities in trust for the
         benefit of the Persons entitled thereto until such sums shall be paid
         to such Persons or otherwise disposed of as herein provided;

                  (2) give the Trustee notice of any default by the Company (or
         any other obligor upon the Securities) in the making of any payment of
         prin cipal (and premium, if any) or interest;

                  (3) at any time during the continuance of any such default,
         upon the written request of the Trustee, forthwith pay to the Trustee
         all sums so held in trust by such Paying Agent; and

                  (4) acknowledge, accept and agree to comply in all respects
         with the provisions of this Indenture relating to the duties, rights
         and obligations of such Paying Agent.

                  The Company may at any time, for the purpose of obtaining the
satisfaction and discharge of this Indenture or for any other purpose, pay, or
by Company Order direct any Paying Agent to pay, to the Trustee all sums held in
trust by the Company or such Paying Agent, such sums to be held by the Trustee
upon the same trusts as those upon which such sums were held by the Company or
such Paying Agent; and, upon such payment by any Paying Agent to the Trustee,
such Paying Agent shall be released from all further liabil ity with respect to
such money.

                  Any money deposited with the Trustee or any Paying Agent, or
then held by the Company, in trust for the payment of the principal of (and
premium, if any) or interest on any Security and remaining unclaimed for two
years after such principal (and premium, if any) or interest has become due and
payable shall be paid to the Company on the Company Request, or (if then held by
the Company) shall be discharged from such trust; and the Holder of such
Security shall thereafter, as an unsecured general creditor, look only to the
Company for payment thereof, and all liability of the Trustee or such Paying
Agent with respect to such trust money, and all liability of the Company as
trustee thereof, shall thereupon cease; PROVIDED, HOWEVER, that the Trustee or
such Paying Agent, before being required to make any such repayment, may at the
expense of the Company cause to be published once, in a newspaper published in
the English language, customarily published on each Business Day and of general
circulation in the Borough of Manhattan, The 



                                      -80-


City of New York, New York, notice that such money remains unclaimed and that,
after a date specified therein, which shall not be less than 30 days from the
date of such publi cation, any unclaimed balance of such money then remaining
will be repaid to the Company.


SECTION 1004.  EXISTENCE.

                  Subject to Article Eight, the Company will do or cause to be
done all things necessary to preserve and keep in full force and effect its
existence, rights (charter and statutory) and franchises; PROVIDED, HOWEVER,
that the Company shall not be required to preserve any such right or franchise
if the Board of Directors shall determine that the preservation thereof is no
longer desirable in the conduct of the business of the Company and that the loss
thereof is not disadvantageous in any material respect to the Holders.


SECTION 1005.  MAINTENANCE OF PROPERTIES AND INSURANCE.

                  The Company will cause all properties used or useful in the
conduct of its business or the business of any Subsidiary, to be maintained and
kept in good condition, repair and working order and supplied with all necessary
equipment and will cause to be made all necessary repairs, renewals,
replacements, betterments and improvements thereof, all as in the judgment of
the Company may be necessary so that the business carried on in connection
therewith may be properly and advantageously conducted at all times; PROVIDED,
HOWEVER, that nothing in this Section shall prevent the Company from
discontinuing the operation or maintenance of any of such properties if such
discontinuance is, as determined in the good faith judgment of the Board of
Directors evidenced by a Board Resolution, desirable in the conduct of its
business or, in the case of the Company, the business of any Subsidiary, and not
disadvantageous in any material respect to the Holders.

                  The Company shall, and shall cause the Subsidiaries of the
Company to, keep at all times all of their properties which are of an insurable
nature insured against loss or damage with insurers believed by the Company to
be responsible to the extent that property of similar character is usually so
insured by corporations similarly situated and owning like properties in
accordance with good business practice.


                                      -81-


SECTION 1006.  PAYMENT OF TAXES AND OTHER CLAIMS.

                  The Company will pay or discharge or cause to be paid or
discharged, before the same shall become delinquent, (1) all taxes, assessments
and governmental charges levied or imposed upon the Company or any Subsidiaries
of the Company or upon the income, profits or property of the Company or any
Subsidiaries, and (2) all lawful claims for labor, materials and supplies which,
if unpaid, might by law become a lien upon the property of the Company or any
Subsidiaries of the Company; PROVIDED, HOWEVER, that the Company shall not be
required to pay or discharge or cause to be paid or discharged any such tax,
assessment, charge or claim whose amount, applicability or validity is being
contested in good faith by appropriate proceedings.


SECTION 1007.  LIMITATION ON CONSOLIDATED DEBT.

                  The Company may not, and may not permit any Restricted
Subsidiary of the Company to, Incur any Debt unless either (a) the ratio of (i)
the aggregate consolidated principal amount of Debt of the Company outstanding
as of the most recent available quarterly or annual balance sheet, after giving
pro forma effect to the Incurrence of such Debt and any other Debt Incurred
since such balance sheet date and the receipt and application of the proceeds
thereof to (ii) Consolidated Cash Flow Available for Fixed Charges for the four
full fiscal quarters next preceding the Incurrence of such Debt for which
consolidated financial statements are available, determined on a pro forma basis
as if any such Debt had been Incurred and the proceeds thereof had been applied
at the beginning of such four fiscal quarters, would be less than 5.5 to 1 for
such four-quarter periods ending on or prior to December 31, 1999 and 5.0 to 1
for such periods ending thereafter, or (b) the Company's Consolidated Capital
Ratio as of the most recent available quarterly or annual balance sheet, after
giving pro forma effect to the Incurrence of such Debt and any other Debt
Incurred since such balance sheet date and the receipt and application of the
proceeds thereof, is less than 2.0 to 1.

                  Notwithstanding the foregoing limitation, the Company and any
Restricted Subsidiary may Incur the following:

                (i) Debt under any one or more Bank Credit Agreements or Vendor
         Financing Facilities in an aggregate principal amount at any one time
         not to exceed $125 million, and any renewal, extension, 



                                      -82-


         refinancing or refunding thereof in an amount which, together with any
         principal amount remaining outstanding or available under all Bank
         Credit Agreements and Vendor Financing Facilities of the Company and
         its Restricted Subsidiaries, plus the amount of any premium required to
         be paid in connection with such refinancing pursuant to the terms of
         any Bank Credit Agreement so refinanced plus the amount of expenses
         incurred in connection with such refinancing, does not exceed the
         aggregate principal amount outstanding or available under all such Bank
         Credit Agreements and Vendor Financing Facilities of the Company and
         its Restricted Subsidiaries immediately prior to such renewal,
         extension, refinancing or refunding;

               (ii) Purchase Money Debt Incurred to finance the construction,
         acquisition or improvement of Telecommunications Assets, PROVIDED that
         the net proceeds of such Purchase Money Debt do not exceed 90% of the
         cost of construction, acquisition or improvement price of the
         applicable Telecommunications Assets;

              (iii) Debt owed by the Company to any Wholly-Owned Restricted
         Subsidiary of the Company or Debt owed by a Restricted Subsidiary of
         the Company to the Company or a Wholly-Owned Restricted Subsidiary of
         the Company; PROVIDED, HOWEVER, that upon either (x) the transfer or
         other disposition by such Wholly-Owned Restricted Subsidiary or the
         Company of any Debt so permitted to a Person other than the Company or
         another Wholly-Owned Restricted Subsidiary of the Company or (y) the
         issuance (other than directors' qualifying shares), sale, lease,
         transfer or other disposition of shares of Capital Stock (including by
         consolidation or merger) of such Wholly-Owned Restricted Subsidiary to
         a Person other than the Company or another such Wholly-Owned Restricted
         Subsidiary, the provisions of this clause (iii) shall no longer be
         applicable to such Debt and such Debt shall be deemed to have been
         Incurred at the time of such transfer or other disposition;

               (iv) Debt Incurred to renew, extend, refinance or refund (each, a
         "refinancing") Debt outstanding at the date of this Indenture or
         Incurred pursuant to the preceding paragraph or clause (ii) of this
         paragraph or the Securities in an aggregate principal amount not to
         exceed the aggregate principal amount of and accrued interest on the
         Debt so 



                                      -83-


         refinanced plus the amount of any premium required to be paid in
         connection with such refinancing pursuant to the terms of the Debt so
         refinanced or the amount of any premium reasonably determined by the
         Company as necessary to accomplish such refinancing by means of a
         tender offer or privately negotiated repurchase, plus the amount of
         expenses of the Company incurred in connection with such refinancing;
         PROVIDED, HOWEVER, that Debt the proceeds of which are used to
         refinance the Securities or Debt which is PARI PASSU to the Securities
         or debt which is subordinate in right of payment to the Securities
         shall only be permitted if (A) in the case of any refinancing of the
         Securities or Debt which is PARI PASSU to the Securities, the
         refinancing Debt is made PARI PASSU to the Securities or subordinated
         to the Securities, and, in the case of any refinancing of Debt which is
         subordinated to the Securities, the refinancing Debt constitutes
         Subordinated Debt and (B) in either case, the refinancing Debt by its
         terms, or by the terms of any agreement or instrument pursuant to which
         such Debt is issued, (x) does not provide for payments of principal of
         such Debt at the stated maturity thereof or by way of a sinking fund
         applicable thereto or by way of any mandatory redemption, defeasance,
         retirement or repurchase thereof by the Company (including any
         redemption, retirement or repurchase which is contingent upon events or
         circumstances, but excluding any retirement required by virtue of
         acceleration of such Debt upon any event of default thereunder), in
         each case prior to the time the same are required by the terms of the
         Debt being refinanced and (y) does not permit redemption or other
         retirement (including pursuant to an offer to purchase made by the
         Company) of such Debt at the option of the holder thereof prior to the
         final stated maturity of the Debt being refinanced, other than a
         redemption or other retirement at the option of the holder of such Debt
         (including pursuant to an offer to purchase made by the Company) which
         is conditioned upon a change substantially similar to the provisions of
         Section 1016 or which is pursuant to provisions substantially similar
         to the provisions of Section 1013;

                (v)  Debt consisting of Permitted Interest Rate and
         Currency Protection Agreements;

               (vi)  Debt outstanding under the Securities;

               (vii) Subordinated Debt invested by (a) a group of employees of 
         the Company, which includes the Chief Executive Officer of the Company,
         who own, directly or indirectly, through an employee stock ownership
         plan or arrangement, shares of the Company's Capital Stock or 



                                      -84-


         (b) any other Person that controls the Company (i) on the Issue Date or
         (ii) after a Change of Control, PROVIDED that the Company is not in
         default with respect to its obligations under Section 1016;

             (viii) Debt consisting of performance and other similar bonds and
         reimbursement obligations Incurred in the ordinary course of business
         securing the performance of contractual, franchise or license
         obligations of the Company or a Restricted Subsidiary, or in respect of
         a letter of credit obtained to secure such performance; and

               (ix) Debt not otherwise permitted to be Incurred pursuant to
         clauses (i) through (viii) above, which, together with any other
         outstanding Debt Incurred pursuant to this clause (ix), has an
         aggregate principal amount (or, in the case of Debt issued at a
         discount, an accreted amount (determined in accordance with generally
         accepted accounting principles) at the time of Incurrence) not in
         excess of $10 million at any time outstanding.

                  For purposes of determining compliance with this Section 1007,
in the event that an item of Debt meets the criteria of more than one of the
types of Debt the Company is permitted to incur pursuant to the foregoing
clauses (i) through (ix), the Company shall have the right, in its sole
discretion, to classify such item of Debt and shall only be required to include
the amount and type of such Debt under the clause permitting the Debt as so
classified. For purposes of determining any particular amount of Debt under such
covenant, Guarantees or Liens with respect to letters of credit supporting Debt
otherwise included in the determination of a particular amount shall not be
included.


SECTION 1008.         LIMITATION ON DEBT AND PREFERRED STOCK OF
                      RESTRICTED SUBSIDIARIES.

                  The Company may not permit any Restricted Subsidiary of the
Company (other than a Restricted Subsidiary that has fully and unconditionally
Guaranteed the Securities on an unsubordinated basis) to Incur or suffer to
exist any Debt or issue any Preferred Stock except:

                (i) Debt or Preferred Stock outstanding on the date of this
         Indenture after giving effect to the application of the proceeds of the
         Securities;



                                      -85-


               (ii) Debt Incurred or Preferred Stock issued to and held by the
         Company or a Wholly-Owned Restricted Subsidiary of the Company
         (provided that such Debt or Preferred Stock is at all times held by the
         Company or a Wholly-Owned Restricted Subsidiary of the Company);

              (iii) Debt Incurred or Preferred Stock issued by a Person prior to
         the time (A) such Person became a Restricted Subsidiary of the Company,
         (B) such Person merges into or consolidates with a Restricted
         Subsidiary of the Company or (C) another Restricted Subsidiary of the
         Company merges into or consolidates with such Person (in a transaction
         in which such Person becomes a Restricted Subsidiary of the Company),
         which Debt or Preferred Stock was not Incurred or issued in
         anticipation of such transaction and was outstanding prior to such
         transaction;

               (iv)  Debt consisting of Permitted Interest Rate and
         Currency Protection Agreements;

                (v)  Debt or Preferred Stock of a Joint Venture;

               (vi) Debt under any one or more Bank Credit Agreements or Vendor
         Financing Facilities (and renewals, extensions, refinancings or
         refundings thereof) which is permitted to be outstanding under clause
         (i) of Section 1007;

              (vii)  Debt consisting of Guarantees of the
         Securities;

             (viii) Debt or Preferred Stock which is exchanged for, or the
         proceeds of which are used to refinance, refund or redeem, any Debt or
         Preferred Stock permitted to be outstanding pursuant to clauses (i),
         (iii) and (ix) hereof (or any extension or renewal thereof) (for
         purposes hereof, a "refinancing"), in an aggregate principal amount, in
         the case of Debt, or with an aggregate liquidation preference, in the
         case of Preferred Stock, not to exceed the aggregate principal amount
         of the Debt so refinanced or the aggregate liquidation preference of
         the Preferred Stock so refinanced, plus the amount of any premium
         required to be paid in connection with such refinancing pursuant to the
         terms of the Debt or Preferred Stock so refinanced or the amount of any
         premium reasonably determined by the Company as necessary to accomplish
         such refinancing by means of a tender offer or privately negotiated
         repurchase, plus the amount of expenses of the Company and the
         Restricted Subsidiary incurred in connection 



                                      -86-


         therewith and provided the Debt or Preferred Stock incurred or issued
         upon such refinancing by its terms, or by the terms of any agreement or
         instrument pursuant to which such Debt or Preferred Stock is Incurred
         or issued, (x) does not provide for payments of principal or
         liquidation value at the stated maturity of such Debt or Preferred
         Stock or by way of a sinking fund applicable to such Debt or Preferred
         Stock or by way of any mandatory redemption, defeasance, retirement or
         repurchase of such Debt or Preferred Stock by the Company or any
         Restricted Subsidiary of the Company (including any redemption,
         retirement or repurchase which is contingent upon events or
         circumstances, but excluding any retirement required by virtue of
         acceleration of such Debt upon an event of default thereunder), in each
         case prior to the time the same are required by the terms of the Debt
         or Preferred Stock being refinanced and (y) does not permit redemption
         or other retirement (including pursuant to an offer to purchase made by
         the Company or a Restricted Subsidiary of the Company) of such Debt or
         Preferred Stock at the option of the holder thereof prior to the stated
         maturity of the Debt or Preferred Stock being refinanced, other than a
         redemption or other retirement at the option of the holder of such Debt
         or Preferred Stock (including pursuant to an offer to purchase made by
         the Company or a Restricted Subsidiary of the Company) which is
         conditioned upon the change of control of the Company pursuant to
         provisions substantially similar to the provisions of Section 1016 or
         which is pursuant to provisions substantially similar to the provisions
         of Section 1013, and PROVIDED, FURTHER, that in the case of any
         exchange or redemption of Preferred Stock of a Restricted Subsidiary of
         the Company, such Preferred Stock may only be exchanged for or redeemed
         with Preferred Stock of such Restricted Subsidiary;

               (ix) Purchase Money Debt Incurred to finance the construction,
         acquisition or improvement of Telecommunications Assets, PROVIDED that
         the net proceeds of such Purchase Money Debt do not exceed 90% of the
         cost of construction, acquisition or improvement price of the
         applicable Telecommunications Assets; and

                (x) Debt not otherwise permitted to be incurred pursuant to
         clauses (i) through (ix) above, which, together with any other
         outstanding Debt incurred pursuant to this clause (x), has an aggregate
         principal amount (or, in the case of Debt issued at a discount, an
         accreted amount (determined in accordance with


                                      -87-




         generally accepted accounting principles) at the time of Incurrence)
         not in excess of $10 million at any time outstanding.


SECTION 1009.  LIMITATION ON RESTRICTED PAYMENTS.

                  The Company (i) may not, directly or indirectly, declare or
pay any dividend, or make any distribution, in respect of its Capital Stock or
to the holders thereof (in their capacity as such), excluding any dividends or
distributions payable solely in shares of its Capital Stock (other than
Disqualified Stock) or in options, warrants or other rights to acquire its
Capital Stock (other than Disqualified Stock); (ii) may not, and may not permit
any Restricted Subsidiary to, purchase, redeem, or otherwise retire or acquire
for value (a) any Capital Stock of the Company or any Related Person of the
Company; or (b) any options, warrants or rights to purchase or acquire shares of
Capital Stock of the Company or any Related Person of the Company or any
securities convertible or exchangeable into shares of Capital Stock of the
Company or any Related Person of the Company; (iii) may not make, or permit any
Restricted Subsidiary to make, any Investment in, or payment on a Guarantee of
any obligation of, any Person, other than the Company or a Restricted Subsidiary
of the Company, except for Permitted Investments; and (iv) may not, and may not
permit any Restricted Subsidiary to, redeem, defease, repurchase, retire or
otherwise acquire or retire for value, prior to any scheduled maturity,
repayment or sinking fund payment, Debt of the Company which is subordinate in
right of payment to the Securities (each of clauses (i) through (iv) being a
"Restricted Payment") if: (1) a Default or an Event of Default shall have
occurred and is continuing; or (2) upon giving effect to such Restricted
Payment, the Company could not Incur at least $1.00 of additional Debt pursuant
to the provisions of the first paragraph of Section 1007; or (3) upon giving
effect to such Restricted Payment, the aggregate of all Restricted Payments from
April 25, 1996 exceeds the sum of: (a) 50% of cumulative Consolidated Net Income
(or, in the case Consolidated Net Income shall be negative, less 100% of such
deficit) since the end of the last full fiscal quarter prior to April 25, 1996
through the last day of the last full fiscal quarter ending immediately
preceding the date of such Restricted Payment; plus (b) $5 million; plus (c)
100% of the net reduction in Investments in any Unrestricted Subsidiary
resulting from payments of interest on Debt, dividends, repayments of loans or
advances, or other transfers of assets, in each case to the Company or any
Restricted Subsidiary of the Company from such Unrestricted Subsidiary



                                       -88-



(except to the extent that any such payment is included in the calculation of
Consolidated Net Income) or from redesignations of Unrestricted Subsidiaries as
Restricted Subsidiaries; PROVIDED that the amount included in this clause (c)
shall not exceed the amount of Investments previously made by the Company and
its Restricted Subsidiaries in such Unrestricted Subsidiary; PROVIDED, FURTHER,
that the Company or a Restricted Subsidiary of the Company may make any
Restricted Payment with the aggregate net proceeds received after April 25,
1996, including the fair value of property other than cash (determined in good
faith by the Board of Directors, as conclusively evidenced by a Board Resolution
filed with the Trustee), as capital contributions to the Company or from the
issuance (other than to a Restricted Subsidiary) of Capital Stock (other than
Disqualified Stock) of the Company and warrants, rights or options on Capital
Stock (other than Disqualified Stock) of the Company and the principal amount of
Debt of the Company that has been converted into Capital Stock (other than
Disqualified Stock and other than by a Restricted Subsidiary) of the Company
after April 25, 1996.

                  Notwithstanding the foregoing, the Company may (i) pay any
dividend on Capital Stock of any class within 60 days after the declaration
thereof if, on the date when the dividend was declared, the Company could have
paid such dividend in accordance with the foregoing provisions; (ii) repurchase
any shares of its Common Equity or options to acquire its Common Equity from
Persons who were formerly officers or employees of the Company, PROVIDED that
the aggregate amount of all such repurchases made pursuant to this clause (ii)
shall not exceed $2 million, plus the aggregate cash proceeds received by the
Company since April 25, 1996 from issuances of its Common Equity or options to
acquire its Common Equity to members, officers, managers, directors and
employees of the Company or any of its Subsidiaries; (iii) the Company and its
Restricted Subsidiaries may refinance any Debt otherwise permitted by clause
(iv) of the second paragraph of Section 1007; and (iv) the Company and its
Restricted Subsidiaries may retire or repurchase any Capital Stock or
Subordinated Debt of the Company in exchange for, or out of the proceeds of the
substantially concurrent sale (other than to a Restricted Subsidiary of the
Company) of, Capital Stock (other than Disqualified Stock) of the Company. If
the Company makes a Restricted Payment which, at the time of the making of such
Restricted Payment, would in the good faith determination of the Company be
permitted under this Indenture, such Restricted Payment shall be deemed to have
been made in compliance with this Indenture notwithstanding any subsequent
adjustments made in good faith to the Company



                                       -89-



financial statements affecting Consolidated Net Income for any period.

         In determining the aggregate amount expended or available for
Restricted Payments in accordance with clause (3) of the first paragraph above,
(1) no amounts expended under clauses (iii) or (iv) of the immediately preceding
paragraph shall be included, (2) 100% of the amounts expended under clauses (i)
and (ii) of the immediately preceding paragraph shall be included, and (3) no
amount shall be credited in respect of issuances of Capital Stock in
transactions under clause (iv) of the immediately preceding paragraph.


SECTION 1010. LIMITATION ON DIVIDEND AND OTHER
              PAYMENT RESTRICTIONS AFFECTING
              RESTRICTED SUBSIDIARIES.        

                  The Company may not, and may not permit any Restricted
Subsidiary to, directly or indirectly, create or otherwise cause or suffer to
exist or become effective any consensual encumbrance or restriction on the
ability of any Restricted Subsidiary of the Company (i) to pay dividends (in
cash or otherwise) or make any other distributions in respect of its Capital
Stock owned by the Company or any other Restricted Subsidiary of the Company or
pay any Debt or other obligation owed to the Company or any other Restricted
Subsidiary; (ii) to make loans or advances to the Company or any other
Restricted Subsidiary; or (iii) to transfer any of its property or assets to the
Company or any other Restricted Subsidiary. Notwithstanding the foregoing, the
Company may, and may permit any Restricted Subsidiary to, suffer to exist any
such encumbrance or restriction (a) pursuant to any agreement in effect on the
Issue Date; (b) pursuant to an agreement relating to any Acquired Debt, which
encumbrance or restriction is not applicable to any Person, or the properties or
assets of any Person, other than the Person so acquired and its Subsidiaries;
(c) pursuant to any one or more Bank Credit Agreements or Vendor Financing
Facilities (and renewals, extensions, refinancings or refundings thereof) which
is permitted to be outstanding under clause (i) of Section 1007, PROVIDED that
such restriction is consistent with, and not materially more restrictive (as
conclusively determined in good faith by the Chief Financial Officer of the
Company), taken as a whole, than, comparable provisions included in similar
agreements or facilities extended to comparable credits engaged in the
Telecommunications Business; (d) pursuant to an agreement effecting a renewal,
refunding or extension of Debt Incurred pursuant to an agreement referred to in
clause (a) or (b)



                                       -90-



above or (e) below, PROVIDED, HOWEVER, that the provisions contained in such
renewal, refunding or extension agreement relating to such encumbrance or
restriction are not materially more restrictive (as conclusively determined in
good faith by the Chief Financial Officer of the Company), taken as a whole,
than the provisions contained in the agreement the subject thereof; (e) in the
case of clause (iii) above, restrictions contained in any security agreement
(including a Capital Lease Obligation) securing Debt of the Company or a
Restricted Subsidiary otherwise permitted under this Indenture, but only to the
extent such restrictions restrict the transfer of the property subject to such
security agreement; (f) in the case of clause (iii) above, customary
nonassignment provisions entered into in the ordinary course of business in
leases and other agreements; (g) any restriction with respect to a Restricted
Subsidiary of the Company imposed pursuant to an agreement which has been
entered into for the sale or disposition of all or substantially all of the
Capital Stock or assets of such Restricted Subsidiary, provided that
consummation of such transaction would not result in a Default or an Event of
Default, that such restriction terminates if such transaction is not consummated
and that such consummation or abandonment of such transaction occurs within one
year of the date such agreement was entered into; (h) pursuant to applicable law
or regulations; (i) pursuant to this Indenture and the Securities; or (j) any
restriction on the sale or other disposition of assets or property securing Debt
as a result of a Permitted Lien on such assets or property.


SECTION 1011.  LIMITATION ON LIENS.

                  The Company may not, and may not permit any Restricted
Subsidiary of the Company to, Incur or suffer to exist any Lien on or with
respect to any property or assets now owned or hereafter acquired to secure any
Debt without making, or causing such Restricted Subsidiary to make, effective
provision for securing the Securities (x) equally and ratably with (or prior to)
such Debt as to such property for so long as such Debt will be so secured or (y)
in the event such Debt is Debt of the Company which is subordinate in right of
payment to the Securities, prior to such Debt as to such property for so long as
such Debt will be so secured.

                  The foregoing restrictions shall not apply to: (i) Liens
existing on the Issue Date and securing Debt outstanding on the Issue Date or
securing the Securities or Liens securing Debt Incurred pursuant to any Bank
Credit



                                       -91-



Agreement or Vendor Financing Facility (whether or not such Bank Credit
Agreement or Vendor Financing Facility was outstanding on the Issue Date); (ii)
Liens securing Debt in an amount which, together with the aggregate amount of
Debt then outstanding or available under the Bank Credit Agreement and Vendor
Financing Facility (or under refinancings or amendments of such agreements),
does not exceed 1.5 times the Company's Consolidated Cash Flow Available for
Fixed Charges for the four full fiscal quarters preceding the Incurrence of such
Lien for which consolidated financial statements are available, determined on a
pro forma basis as if such Debt had been Incurred and the proceeds thereof had
been applied at the beginning of such four fiscal quarters; (iii) Liens in favor
of the Company or any Wholly-Owned Restricted Subsidiary of the Company; (iv)
Liens on real or personal property of the Company or a Restricted Subsidiary of
the Company acquired, constructed or constituting improvements made after the
Issue Date to secure Purchase Money Debt which is Incurred for the construction,
acquisition and improvement of Telecommunications Assets and is otherwise
permitted under this Indenture, PROVIDED, HOWEVER, that (a) the net proceeds of
any Debt secured by such a Lien does not exceed 100% of such purchase price or
cost of construction or improvement of the property subject to such Lien, (b)
such Lien attaches to such property prior to, at the time of or within 180 days
after the acquisition, completion of construction or commencement of operation
of such property and (c) such Lien does not extend to or cover any property
other than the property (or identifiable portions thereof) acquired, constructed
or constituting the improvements made with the proceeds of such Purchase Money
Debt (it being understood and agreed that all Debt owed to any single lender or
group of lenders or outstanding under any single credit facility shall be
considered a single Purchase Money Debt, whether drawn at one time or from time
to time); (v) Liens to secure Acquired Debt, PROVIDED, HOWEVER, that (a) such
Lien attaches to the acquired asset prior to the time of the acquisition of such
asset and (b) such Lien does not extend to or cover any other asset; (vi) Liens
to secure Debt Incurred to extend, renew, refinance or refund (or successive
extensions, renewals, refinancings or refundings), in whole or in part, Debt
secured by any Lien referred to in the foregoing clauses (i), (ii), (iv) and (v)
so long as such Lien does not extend to any other property and the principal
amount of Debt so secured is not increased except as otherwise permitted under
clause (iv) of Section 1007; (vii) Liens securing Debt not otherwise permitted
by the foregoing clauses (i) through (vi) in an amount not to exceed 5% of the
Company's Consolidated Tangible Assets



                                       -92-



determined as of the most recent available quarterly or annual balance sheet;
and (viii) Permitted Liens.


SECTION 1012.   LIMITATION ON SALE AND LEASEBACK
                TRANSACTIONS.                   

                  The Company may not, and may not permit any Restricted
Subsidiary to, enter into any Sale and Leaseback Transaction unless (i) the
Company or such Restricted Subsidiary would be entitled to Incur a Lien to
secure Debt by reason of the provisions of Section 1011, equal in amount to the
Attributable Value of the Sale and Leaseback Transaction without equally and
ratably securing the Securities; or (ii) the Sale and Leaseback Transaction is
treated as an Asset Disposition and all of the conditions of Section 1013
(including the provisions concerning the application of Net Available Proceeds)
are satisfied with respect to such Sale and Leaseback Transaction, treating all
of the consideration received in such Sale and Leaseback Transaction in the same
manner as consideration in respect of an Asset Disposition for purposes of such
covenant.


SECTION 1013.  LIMITATION ON ASSET DISPOSITIONS.

                  (a) The Company may not, and may not permit any Restricted
Subsidiary to, make any Asset Disposition in one or more related transactions
occurring within any 12-month period unless: (i) the Company or the Restricted
Subsidiary, as the case may be, receives consideration for such disposition at
least equal to the fair market value for the assets sold or disposed of as
determined by the Board of Directors in good faith and evidenced by a Board
Resolution filed with the Trustee, which determination shall be conclusive; (ii)
at least 75% of the consideration for such disposition consists of (1) cash or
readily marketable cash equivalents or the assumption of Debt of the Company
(other than Debt that is subordinated to the Securities) or of the Restricted
Subsidiary and release from all liability on the Debt assumed; (2)
Telecommunications Assets; or (3) shares of publicly-traded Voting Stock of any
Person engaged in the Telecommunications Business in the United States; and
(iii) all Net Available Proceeds, less any amounts invested within 360 days of
such disposition in new Telecommunications Assets, are applied within 360 days
of such disposition (1) first, to the permanent repayment or reduction of Debt
then outstanding under any Bank Credit Agreement or Vendor Financing Facility,
to the extent such agreements would require such application or prohibit
payments pursuant to clause (2) following, (2) second, to



                                       -93-



the extent of remaining Net Available Proceeds, to make an Offer to Purchase
outstanding Securities at 100% of their principal amount plus accrued interest
to the date of purchase and, to the extent required by the terms thereof, any
other Debt of the Company that is pari passu with the Securities at a price no
greater than 100% of the principal amount thereof plus accrued interest to the
date of purchase, and (3) third, to the extent of any remaining Net Available
Proceeds following the completion of the Offer to Purchase, to the repayment of
other Debt of the Company or Debt of a Restricted Subsidiary of the Company, to
the extent permitted under the terms thereof. To the extent any Net Available
Proceeds remain after such uses, the Company and its Restricted Subsidiaries may
use such amounts for any purposes not prohibited by this Indenture.

                  (b) The Company will mail the Offer for an Offer to Purchase
required pursuant to Section 1013(a) not more than 360 days after consummation
of the disposition referred to in Section 1013(a). The aggregate principal
amount of the Securities to be offered to be purchased pursuant to the Offer to
Purchase shall equal the Net Available Proceeds available therefor pursuant to
Clause (iii)(2) of Section 1013(a) (rounded down to the next lowest integral
multiple of $1,000). Each Holder shall be entitled to tender all or any portion
of the Securities owned by such Holder pursuant to the Offer to Purchase,
subject to the requirement that any portion of a Security tendered must be
tendered in an integral multiple of $1,000 principal amount.

                  The Company shall not be entitled to any credit against its
obligations under this Section 1013 for the principal amount of any Securities
acquired or redeemed by the Company otherwise than pursuant to the Offer to
Purchase pursuant to this Section 1013.

                  (c) Not later than the date of the Offer with respect to an
Offer to Purchase pursuant to this Section 1013, the Company shall deliver to
the Trustee an Officers' Certificate as to (i) the Purchase Amount, (ii) the
alloca tion of the Net Available Proceeds from the Asset Disposi tion pursuant
to which such Offer is being made, including, if amounts are invested in
Telecommunication Assets, the amount of the assets acquired and (iii) the
compliance of such allocation with the provisions of Section 1013(a).

                  The Company and the Trustee shall perform their respective
obligations specified in the Offer for the Offer to Purchase. On or prior to the
Purchase Date, the Company shall (i) accept for payment (on a pro rata basis, if
necessary)



                                       -94-



Securities or portions thereof tendered pursuant to the Offer, (ii) deposit with
the Paying Agent (or, if the Company is acting as its own Paying Agent,
segregate and hold in trust as provided in Section 1003) money sufficient to pay
the purchase price of all Securities or portions thereof so accepted and (iii)
deliver or cause to be delivered to the Trustee all Securities so accepted
together with an Officers' Certificate stating the Securities or portions
thereof accepted for payment by the Company. The Paying Agent (or the Company,
if so acting) shall promptly mail or deliver to Holders of Securities so
accepted payment in an amount equal to the purchase price, and the Trustee shall
promptly authenticate and mail or deliver to such Holders a new Security of like
tenor equal in principal amount to any unpurchased portion of the Security
surren dered. Any Security not accepted for payment shall be promptly mailed or
delivered by the Company to the Holder thereof.

                  (d) Notwithstanding the foregoing, this Section 1013 shall not
apply to any Asset Disposition which constitutes a transfer, conveyance, sale,
lease or other disposition of all or substantially all of the Company's
properties or assets within the meaning of Section 801 hereof.


SECTION 1014.  LIMITATION ON ISSUANCES AND SALES OF
               CAPITAL STOCK OF RESTRICTED SUBSIDIARIES.

                  The Company may not, and may not permit any Restricted
Subsidiary of the Company to, issue, transfer, convey, sell or otherwise dispose
of any shares of Capital Stock of a Restricted Subsidiary of the Company or
securities convertible or exchangeable into, or options, warrants, rights or any
other interest with respect to, Capital Stock of a Restricted Subsidiary of the
Company to any person other than the Company or a Wholly-Owned Restricted
Subsidiary of the Company except (i) in a transaction consisting of a sale of
Capital Stock of such Restricted Subsidiary owned by the Company or any
Restricted Subsidiary of the Company and that complies with the provisions of
Section 1013 to the extent such provisions apply; (ii) if required, the
issuance, transfer, conveyance, sale or other disposition of directors'
qualifying shares; (iii) in a transaction in which, or in connection with which,
the Company or a Restricted Subsidiary acquires at the same time sufficient
Capital Stock of such Restricted Subsidiary to at least maintain the same
percentage ownership interest it had prior to such transaction; (iv)
constituting the issuance of Preferred Stock permitted by



                                       -95-



the provisions of Section 1008; and (v) Disqualified Stock issued in exchange
for, or upon conversion of, or the proceeds of the issuance of which are used to
redeem, refinance, replace or refund shares of Disqualified Stock of such
Restricted Subsidiary, provided that the amounts of the redemption obligations
of such Disqualified Stock shall not exceed the amounts of the redemption
obligations of, and such Disqualified Stock shall have redemption obligations no
earlier than those required by, the Disqualified Stock being exchanged,
converted, redeemed, refinanced, replaced or refunded.


SECTION 1015.  TRANSACTIONS WITH AFFILIATES
               AND RELATED PERSONS.        

                  The Company may not, and may not permit any Restricted
Subsidiary of the Company to, enter into any transaction (or series of related
transactions) with an Affiliate or Related Person of the Company (other than the
Company or a Wholly-Owned Restricted Subsidiary of the Company), including any
Investment, but excluding transactions pursuant to employee compensation
arrangements approved by the Board of Directors, either directly or indirectly,
unless such transaction is on terms no less favorable to the Company or such
Restricted Subsidiary than those that could be obtained in a comparable
arm's-length transaction with an entity that is not an Affiliate or Related
Person and is in the best interests of such Company or such Restricted
Subsidiary. For any transaction that involves in excess of $1 million but less
than or equal to $5 million, the Chief Executive Officer of the Company shall
determine that the transaction satisfies the above criteria and shall evidence
such a determination by an Officer's Certificate filed with the Trustee. For any
transaction that involves in excess of $5 million, the Company shall also obtain
an opinion from a nationally recognized expert with experience in appraising the
terms and conditions, taken as a whole, of the type of transaction (or series of
related transactions) for which the opinion is required stating that such
transaction (or series of related transactions) is on terms and conditions,
taken as a whole, no less favorable to the Company or such Restricted Subsidiary
than those that could be obtained in a comparable arm's-length transaction with
an entity that is not an Affiliate or Related Person of the Company, which
opinion shall be filed with the Trustee. This covenant shall not apply to
Investments by an Affiliate or a Related Person of the Company in the Capital
Stock (other than Disqualified Stock) of the Company or any Restricted
Subsidiary of the Company.



                                       -96-



SECTION 1016.  CHANGE OF CONTROL.

                  (a) Within 30 days of the occurrence of a Change of Control,
the Company will be required to make an Offer to Purchase all Outstanding
Securities at a purchase price equal to 101% of their principal amount plus
accrued and unpaid interest to the date of purchase.

                  (b) The Company and Trustee shall perform their respective
obligations specified in the Offer for the Offer to Purchase. On or prior to the
Purchase Date, the Company shall (i) accept for payment Securities or portions
thereof tendered pursuant to the Offer, (ii) deposit with the Paying Agent (or,
if the Company is acting as its own Paying Agent, segregate and hold in trust as
provided in Section 1003) money sufficient to pay the purchase price of all
Securities or portions thereof so accepted and (iii) deliver or cause to be
delivered to the Trustee all Securities so accepted together with an Officers'
Certificate stating the Securities or portions thereof accepted for payment by
the Company. The Paying Agent shall promptly mail or deliver to Holders of
Securities so accepted payment in an amount equal to the purchase price, and the
Trustee shall promptly authenticate and mail or deliver to such Holders a new
Security or Securities equal in principal amount to any unpurchased portion of
the Security surrendered as requested by the Holder. Any Security not accepted
for payment shall be promptly mailed or delivered by the Company to the Holder
thereof.

                  (c) A "Change of Control" will be deemed to have occurred at
such time as either (a) any Person or any Persons acting together that would
constitute a "group" (a "Group") for purposes of Section 13(d) of the Exchange
Act, or any successor provision thereto (other than Eagle River, Mr. Craig O.
McCaw and their respective Affiliates or an underwriter engaged in a firm
commitment underwriting on behalf of the Company), shall beneficially own
(within the meaning of Rule 13d-3 under the Exchange Act, or any successor
provision thereto) more than 50% of the aggregate voting power of all classes of
Voting Stock of the Company; or (b) neither Mr. Craig O. McCaw nor any person
designated by him to the Company as acting on his behalf shall be a director of
the Company; or (c) during any period of two consecutive years, individuals who
at the beginning of such period constituted the Board of Directors (together
with any new directors whose election by the Board of Directors or whose
nomination for election by the shareholders of the Company was proposed by a
vote of a majority of the directors of the Company then still in office who were
either directors at the beginning of such period or whose



                                       -97-



election or nomination for election was previously so approved) cease for any
reason to constitute a majority of the Board of Directors then in office.

                  (d) In the event that the Company makes an Offer to Purchase
the Securities, the Company intends to comply with any applicable securities
laws and regulations, including any applicable requirements of Section 14(e) of,
and Rule 14e-1 under, the Exchange Act.

                  (e) Unless the Company defaults in the payment of the Purchase
Price, any Security accepted for payment pursuant to an Offer to Purchase shall
cease to accrue interest after the Purchase Date.


SECTION 1017.  PROVISION OF FINANCIAL INFORMATION.

                  The Company has agreed to file with the Trustee, within 15
days after it files them with the Commission, copies of the SEC Reports. In the
event the Company shall cease to be required to file SEC Reports pursuant to the
Exchange Act, the Company will nevertheless continue to file such reports with
the Commission (unless the Commission will not accept such a filing) and the
Trustee. The Company will furnish copies of the SEC Reports to the Holders of
Securities at the time the Company is required to file the same with the Trustee
and will make such information available to investors who request it in writing.


SECTION 1018.  STATEMENT BY OFFICERS AS TO DEFAULT.

                  (a) The Company will deliver to the Trustee, within 90 days
after the end of each quarter of each fiscal year of the Company ending after
the date hereof, an Officers' Certificate, stating whether or not to the best
knowledge of the signers thereof the Company is in default in the performance
and observance of any of the terms, provisions and conditions of this Indenture
and if the Company shall be in default, specifying all such defaults and the
nature and status thereof of which they may have knowledge.

                  (b) The Company shall deliver to the Trustee, as soon as
possible and in any event within 10 days after the Company becomes aware of the
occurrence of a Default or an Event of Default, an Officers' Certificate setting
forth the details of such Default or Event of Default and the action which the
Company proposes to take with respect thereto.



                                       -98-



SECTION 1019.  WAIVER OF CERTAIN COVENANTS.

                  The Company may omit in any particular instance to comply with
any covenant or condition set forth in Sections 1004 to 1017, inclusive, if
before or after the time for such compliance the Holders of at least a majority
in aggregate principal amount of the Outstanding Securities shall, by Act of
such Holders, either waive such compliance in such instance or generally waive
compliance with such covenant or condition, but no such waiver shall extend to
or affect such covenant or condition except to the extent so expressly waived,
and, until such waiver shall become effective, the obligations of the Company
and the duties of the Trustee in respect of any such covenant or condition shall
remain in full force and effect.


                                 ARTICLE ELEVEN

                            REDEMPTION OF SECURITIES

SECTION 1101.  RIGHT OF REDEMPTION.

                  (a) The Securities may be redeemed prior to October 1, 2002
only in the event that on or before October 1, 2000 the Company receives net
proceeds from a sale of its Common Equity, in which case the Company may, at its
option, use all or a portion of any such net proceeds to redeem Securities in a
principal amount of up to an aggregate amount equal to 331/3% of the original
principal amount of the Securities PROVIDED, HOWEVER, that Securities in an
amount equal to at least $266.7 million remain outstanding after such
redemption. Such redemption must occur on a Redemption Date within 90 days of
any such sale and upon not less than 30 nor more than 60 days' notice by mail to
each Holder of Securities to be redeemed at such Holder's address appearing in
the Security Register, in amounts of $1,000 or an integral multiple of $1,000 at
a Redemption Price of 109.625% of their principal amount plus accrued and unpaid
interest, if any, to but excluding the Redemption Date (subject to the right of
Holders of record on the relevant Regular Record Date to receive interest due on
an Interest Payment Date that is on or prior to the Redemption Date).

                  (b) The Securities further may be redeemed, as a whole or in
part, at the election of the Company, at any time on or after October 1, 2002
and prior to maturity, upon not less than 30 nor more than 60 days' notice by
mail to each Holder of Securities to be redeemed at such Holder's address
appearing in the Security Register, in amounts of $1,000 or an integral multiple
of $1,000, at the Redemption



                                       -99-



Prices specified in the form of Security hereinbefore set forth, together with
accrued and unpaid interest to, but excluding, the Redemption Date (subject to
the right of Holders of record on the relevant Regular Record Date to receive
interest due on an Interest Payment Date that is on or prior to the Redemption
Date).


SECTION 1102.  APPLICABILITY OF ARTICLE.

                  Redemption of Securities at the election of the Company, as
permitted or required by any provision of this Indenture, shall be made in
accordance with such provision and this Article.


SECTION 1103.  ELECTION TO REDEEM; NOTICE TO TRUSTEE.

                  The election of the Company to redeem any Securi ties pursuant
to Section 1101 shall be evidenced by Board Resolution. In case of any
redemption at the election of the Company of less than all the Securities, the
Company shall, at least 60 days prior to the Redemption Date fixed by the
Company (unless a shorter notice shall be satisfac tory to the Trustee), notify
the Trustee in writing of such Redemption Date and of the principal amount of
Securities to be redeemed. In the case of any redemption of Securities prior to
the expiration of any restriction on such redemption provided in the terms of
such Securities or elsewhere in this Indenture, the Company shall furnish the
Trustee with an Officers' Certificate evidencing compliance with such
restriction.

SECTION 1104.  SECURITIES TO BE REDEEMED PRO RATA.

                  If less than all the Securities are to be redeemed in any
redemption, the Securities to be redeemed shall be selected by the Trustee by
prorating, as nearly as may be practicable, the principal amount of Securities
to be redeemed. In any proration pursuant to this Section, the Trustee shall
make such adjustments, reallocations and eliminations as it shall deem proper
(and in compliance with the requirements of the principal national securities
exchange, if any, on which the Securities are listed) to the end that the
principal amount of Securities so prorated shall be $1,000 or a multiple
thereof, by increasing or decreasing or eliminating the amount which would be
allocable to any Holder on the basis of exact proportion by an amount not
exceeding $1,000. The Trustee in its discretion may determine the particular
Securities (if there



                                      -100-



are more than one) registered in the name of any Holder which are to be
redeemed, in whole or in part.

                  The Trustee shall promptly notify the Company and each
Security Registrar (other than the Trustee) in writing of the Securities
selected for redemption and, in the case of any Securities selected for partial
redemption, the principal amount thereof to be redeemed.

                  For all purposes of this Indenture, unless the context
otherwise requires, all provisions relating to the redemption of Securities
shall relate, in the case of any Securities redeemed or to be redeemed only in
part, to the portion of the principal amount of such Securities which has been
or is to be redeemed.


SECTION 1105.  NOTICE OF REDEMPTION.

                  Notice of redemption shall be given by first-class mail,
postage prepaid, mailed not less than 30 nor more than 60 days prior to the
Redemption Date, to each Holder of Securities to be redeemed, at such Holder's
address appearing in the Security Register.

                  All notices of redemption shall state:

                  (1)  the Redemption Date,

                  (2)  the Redemption Price,

                  (3) whether the redemption is being made pursuant to Section
         1101(a) or (b) and, if being made pursuant to Section 1101(a), a brief
         statement setting forth the Company's right to effect such redemption
         and the Company's basis therefor,

                  (4) if less than all the Outstanding Securities are to be
         redeemed, the identification (and, in the case of partial redemption of
         any Securities, the principal amounts) of the particular Securities to
         be redeemed,

                  (5) that on the Redemption Date the Redemption Price will
         become due and payable upon each such Security to be redeemed and that
         interest thereon will cease to accrue on and after said date,

                  (6) the place or places where such Securities are to be
         surrendered for payment of the Redemption Price,



                                      -101-



                  (7) that in the case that a Security is only redeemed in part,
         the Company shall execute and the Trustee shall authenticate and
         deliver to the Holder of such Security without service charge, a new
         Security or Securities in an aggregate amount equal to the unredeemed
         portion of the Security,

                  (8)      the aggregate principal amount of Securities
         being redeemed, and

                  (9) the CUSIP number or numbers of the Securities being
         redeemed.

                  Notice of redemption of Securities to be redeemed at the
election of the Company shall be given by the Company or, if request is made to
the Trustee no less than 35 days prior to the Redemption Date, by the Trustee in
the name and at the expense of the Company.


SECTION 1106.  DEPOSIT OF REDEMPTION PRICE.

                  Prior to any Redemption Date, the Company shall deposit with
the Trustee or with a Paying Agent (or, if the Company is acting as its own
Paying Agent, segregate and hold in trust as provided in Section 1003) an amount
of money sufficient to pay the Redemption Price of, and (except if the
Redemption Date shall be an Interest Payment Date) accrued and unpaid interest
on, all the Securities which are to be redeemed on that date.

SECTION 1107.  SECURITIES PAYABLE ON REDEMPTION DATE.

                  Notice of redemption having been given as aforesaid, the
Securities so to be redeemed shall, on the Redemption Date, become due and
payable at the Redemption Price therein specified, and from and after such date
(unless the Company shall default in the payment of the Redemption Price and
accrued and unpaid interest) such Securities shall cease to bear interest. Upon
surrender of any such Security for redemption in accordance with said notice,
such Security shall be paid by the Company at the Redemption Price, together
with accrued and unpaid interest to the Redemption Date; PROVIDED, HOWEVER, that
installments of interest whose Stated Maturity is on or prior to the Redemption
Date shall be payable to the Holders of such Securities, or one or more
Predecessor Securities, registered as such at the close of business on the
relevant Record Dates according to their terms and the provisions of Section
307.



                                      -102-



                  If any Security called for redemption shall not be so paid
upon surrender thereof for redemption, the principal (and premium, if any)
shall, until paid, bear interest from the Redemption Date at the rate provided
by the Security.


SECTION 1108.  SECURITIES REDEEMED IN PART.

                  Any Security which is to be redeemed only in part shall be
surrendered at an office or agency of the Company designated for that purpose
pursuant to Section 1002 (with, if the Company or the Trustee so requires, due
endorsement by, or a written instrument of transfer in form satisfactory to the
Company and the Trustee duly executed by, the Holder thereof or his attorney
duly authorized in writing), and the Company shall execute, and the Trustee
shall authenticate and deliver to the Holder of such Security without service
charge, a new Security or Securities of like tenor, of any authorized
denomination as requested by such Holder, in aggregate principal amount equal to
and in exchange for the unredeemed portion of the principal of the Security so
surrendered. If a Global Security is so surrendered, such new Security shall
also be a Global Security.


                                 ARTICLE TWELVE

                       Defeasance and Covenant Defeasance

SECTION 1201.  COMPANY'S OPTION TO EFFECT DEFEASANCE OR
               COVENANT DEFEASANCE.                   

                  The Company may, at its option by Board Resolution at any time
(subject to 10-day prior written notification to the Trustee), elect to have
either Section 1202 or Section 1203 applied to the Outstanding Securities upon
compliance with the conditions set forth below in this Article Twelve.


SECTION 1202.  DEFEASANCE AND DISCHARGE.

                  Upon the Company's exercise of the option provided in Section
1201 applicable to this Section, the Company shall be deemed to have been
discharged from its obligations with respect to the Outstanding Securities on
the date the conditions set forth below are satisfied (hereinafter,
"defeasance"). For this purpose, such defeasance means that the Company shall be
deemed to have paid and discharged the entire indebtedness represented by the
Outstanding Securities and to have satisfied all its other obligations



                                      -103-



under such Securities and this Indenture insofar as such Securities are
concerned (and the Trustee, at the expense of the Company, shall execute proper
instruments acknowledging the same), except for the following which shall
survive until otherwise terminated or discharged hereunder: (A) the rights of
Holders of Outstanding Securities to receive, solely from the trust fund
described in Section 1204 and as more fully set forth in such Section, payments
in respect of the principal of (and premium, if any) and interest on such
Securities when such payments are due, (B) the Company's obligations with
respect to such Securities under Sections 304, 305, 306, 1002 and 1003, (C) the
rights, powers, trusts, duties and immunities of the Trustee hereunder and (D)
this Article Twelve. Subject to compliance with this Article Twelve, the Company
may exercise its option under this Section 1202 notwithstanding the prior
exercise of its option under Section 1203.


SECTION 1203.  COVENANT DEFEASANCE.

                  Upon the Company's exercise of the option provided in Section
1201 applicable to this Section (i) the Company shall be released from its
obligations under Sections 1005 through 1017, inclusive, and Clauses (3) and (4)
of Section 801, (ii) the occurrence of an event specified in Sections 501(3),
501(4) (with respect to Clauses (3) and (4) of Section 801), and 501 (5) (with
respect to Sections 1005 through 1017, inclusive) shall not be deemed to be an
Event of Default, on and after the date the conditions set forth below are
satisfied (hereinafter, "covenant defeasance"). For this purpose, such covenant
defeasance means that the Company may omit to comply with and shall have no
liability in respect of any term, condition or limitation set forth in any such
Section or Article, whether directly or indirectly by reason of any reference
elsewhere herein to any such Section or Article or by reason of any reference in
any such Section or Article to any other provision herein or in any other
document, but the remainder of this Indenture and such Securities shall be
unaffected thereby.


SECTION 1204.  CONDITIONS TO DEFEASANCE OR
               COVENANT DEFEASANCE.

                  The following shall be the conditions to application of
either Section 1202 or Section 1203 to the Outstanding Securities:

                  (1) The Company shall irrevocably have deposited or caused to
         be deposited with the Trustee as trust



                                      -104-



         funds in trust for the purpose of making the following payments,
         specifically pledged as security for, and dedicated solely to, the
         benefit of the Holders of such Securities, (A) money in an amount, or
         (B) U.S. Government Obligations which through the scheduled payment of
         principal and interest in respect thereof in accordance with their
         terms will provide, not later than one day before the due date of any
         payment, money in an amount, or (C) a combination thereof, sufficient,
         in the opinion of a nationally recognized firm of independent certified
         public accountants expressed in a written certification thereof
         delivered to the Trustee, to pay and discharge, and which shall be
         applied by the Trustee to pay and discharge, the principal of, premium,
         if any, and each installment of interest on the Securities on the
         Stated Maturity of such principal or installment of interest on the day
         on which such payments are due and payable in accordance with the terms
         of this Indenture and of such Securities. For this purpose, "U.S.
         Government Obligations" means securities that are (x) direct
         obligations of the United States of America for the payment of which
         its full faith and credit is pledged or (y) obligations of a Person
         controlled or supervised by and acting as an agency or instrumentality
         of the United States of America the payment of which is unconditionally
         guaranteed as a full faith and credit obligation by the United States 
         of America, which, in either case, are not callable or redeemable at 
         the option of the issuer thereof, and shall also include
         a depositary receipt issued by a bank (as defined in Section 3(a)(2) of
         the Securities Act) as custodian with respect to any such U.S.
         Government Obligation or a specific payment of principal of or interest
         on any such U.S. Government Obligation held by such custodian for the
         account of the holder of such depositary receipt, provided that (except
         as required by law) such custodian is not authorized to make any
         deduction from the amount payable to the holder of such depositary
         receipt from any amount received by the custodian in respect of the
         U.S. Government Obligation or the specific payment of principal of or
         interest on the U.S. Government Obligation evidenced by such depositary
         receipt.

                  (2) No Default or Event of Default shall have occurred and be
         continuing on the date of such deposit or, insofar as subsections
         501(8) and (9) are concerned, at any time during the period ending on
         the 91st day after the date of such deposit (it being



                                      -105-



         understood that this condition shall not be deemed satisfied until the
         expiration of such period).

                  (3) Such defeasance or covenant defeasance shall not cause the
         Trustee to have a conflicting interest as defined in Section 608 and
         for purposes of the Trust Indenture Act with respect to any securities
         of the Company.

                  (4) Such defeasance or covenant defeasance shall not result in
         a breach or violation of, or constitute a default under, this Indenture
         or any other agreement or instrument to which the Company is a party or
         by which it is bound.

                  (5) The Company shall have delivered to the Trustee an
         Officers' Certificate and an Opinion of Counsel, each stating that all
         conditions precedent provided for relating to either the defeasance
         under Section 1202 or the covenant defeasance under Section 1203 (as
         the case may be) have been complied with.

                  (6) In the case of an election under Section 1202, the Company
         shall have delivered to the Trustee an Opinion of Counsel stating that
         (x) the Company has received from, or there has been published by, the
         Internal Revenue Service a ruling, or (y) since the date of this
         Indenture there has been a change in the applicable Federal income tax
         law, in either case to the effect that, and based thereon such opinion
         shall confirm that, the Holders of the Outstanding Securities will not
         recognize income, gain or loss for Federal income tax purposes as a
         result of such deposit, defea sance and discharge and will be subject
         to Federal income tax on the same amounts, in the same manner and at
         the same times as would have been the case if such deposit, defeasance
         and discharge had not occurred.

                  (7) In the case of an election under Section 1203, the Company
         shall have delivered to the Trustee an Opinion of Counsel to the effect
         that the Holders of the Outstanding Securities will not recognize
         income, gain or loss for Federal income tax purposes as a result of
         such deposit and covenant defeasance and will be subject to Federal
         income tax on the same amounts, in the same manner and at the same
         times as would have been the case if such covenant defeasance had not
         occurred.



                                      -106-



                  (8) The Company shall have delivered to the Trustee an Opinion
         of Counsel to the effect that such deposit and defeasance or covenant
         defeasance shall not result in the trust arising from such deposit
         constituting an investment company as defined in the Investment
         Company Act of 1940, as amended, or such trust shall be qualified under
         such act or exempt from regulation thereunder.


SECTION 1205.  DEPOSITED MONEY AND U.S. GOVERNMENT
               OBLIGATIONS TO BE HELD IN TRUST;
               OTHER MISCELLANEOUS PROVISIONS.

                  Subject to the provisions of the last paragraph of Section
1003, all money and U.S. Government Obligations (including the proceeds thereof)
deposited with the Trustee (or other qualifying trustee--collectively, for
purposes of this Section 1205, the "Trustee") pursuant to Section 1204 in
respect of the Securities shall be held in trust and applied by the Trustee, in
accordance with the provisions of such Securities and this Indenture, to the
payment, either directly or through any Paying Agent (including the Company
acting as its own Paying Agent) as the Trustee may determine, to the Holders of
such Securities, of all sums due and to become due thereon in respect of
principal (and premium, if any) and interest, but such money need not be
segregated from other funds except to the extent required by law.

                  The Company shall pay and indemnify the Trustee against any
tax, fee or other charge imposed on or assessed against the U.S. Government
Obligations deposited pursuant to Section 1204 or the principal and interest
received in respect thereof other than any such tax, fee or other charge which
by law is for the account of the Holders of the Outstanding Securities.

                  Anything in this Article Twelve to the contrary
notwithstanding, the Trustee shall deliver or pay to the Company from time to
time upon Company Request any money or U.S. Government Obligations held by it as
provided in Section 1204 which, in the opinion of a nationally recognized
accounting firm expressed in a written certification thereof delivered to the
Trustee, are in excess of the amount thereof which would then be required to be
deposited to effect an equivalent defeasance or covenant defeasance.



                                      -107-



SECTION 1206.  REINSTATEMENT.

                  If the Trustee or the Paying Agent is unable to apply any
money in accordance with Section 1202 or 1203 by reason of any order or judgment
of any court or governmental authority enjoining, restraining or otherwise
prohibiting such application, then the Company's obligations under this
Indenture and the Securities shall be revived and reinstated as though no
deposit had occurred pursuant to this Article Twelve until such time as the
Trustee or Paying Agent is permitted to apply all such money in accordance with
Section 1202 and 1203; PROVIDED, HOWEVER, that if the Company makes any payment
of principal of (and premium, if any) any Security following the reinstatement
of its obligations, the Company shall be subrogated to the rights of the Holders
of such Securities to receive such payment from the money held by the Trustee or
the Paying Agent.


SECTION 1207.  REPAYMENT TO COMPANY.

                  Any money deposited with the Trustee or any Paying Agent, or
then held by the Company, in trust for the payment of the principal of, premium,
if any, or interest on any Security and remaining unclaimed for two years after
such principal, and premium, if any, or interest has become due and payable
shall be paid to the Company on its written request or (if then held by the
Company) shall be discharged from such trust; and the Holder of such security
shall thereafter, as a creditor, look only to the Company for payment thereof,
and all liability of the Trustee or such Paying Agent with respect to such trust
money, and all liability of the Company as trustee thereof, shall thereupon
cease; PROVIDED, HOWEVER, that the Trustee or such Paying Agent, before being
required to make any such repayment, may at the expense of the Company cause to
be published once, in the New York Times and The Wall Street Journal (national
edition), notice that such money remains unclaimed and that, after a date
specified therein, which shall not be less than 30 days from the date of such
notification or publication, any unclaimed balance of such money then remaining
will be repaid to the Company.

                      ---------------------------


                  This instrument may be executed in any number of counterparts,
each of which so executed shall be deemed to be an original, but all such
counterparts shall together constitute but one and the same instrument.



                                      -108-



                  IN WITNESS WHEREOF, the parties hereto have caused this
Indenture to be duly executed and attested, and the Trustee has caused its seal
to be hereunto affixed and attested, all as of the day and year first above
written.


                                            NEXTLINK Communications, Inc.

                                            By
                                              ----------------------------------
                                              Name: R. Bruce Easter, Jr.
                                              Title: Vice President, General
                                                     Counsel and Secretary



Attest:

- --------------------------------
Name:
Title:


                                            UNITED STATES TRUST COMPANY
                                              OF NEW YORK


                                            By
                                              ----------------------------------
                                              Name:
                                              Title:

[SEAL]

Attest:

- --------------------------------
Name:
Title:



                                      -109-



STATE OF NEW YORK  )
                       ss.:
COUNTY OF NEW YORK )

                  On this    day of October, 1997, before me personally 
appeared R. Bruce Easter, Jr., to me known, who, being duly sworn, did depose 
and say that he is the Vice President of NEXTLINK Communications, Inc., one 
of the corporations described in and which executed the foregoing instrument, 
and duly acknowledged to me that he executed the same by authority of the 
Board of Directors of said corporation.

                                                  ------------------------------
                                                          Notary Public




STATE OF NEW YORK  )
                       ss.:
COUNTY OF NEW YORK )

                  On this day of October, 1997, before me personally appeared ,
to me known, who, being duly sworn, did depose and say that he is the Vice
President of United States Trust Company of New York, one of the corporations
described in and which executed the foregoing instrument, and duly acknowledged
to me that he executed the same by authority of the Board of Directors of said
corporation.

                                                  ------------------------------
                                                           Notary Public