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                                                                     Exhibit 4.4

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                               GLOBIX CORPORATION
                 (FORMERLY KNOWN AS BELL TECHNOLOGY GROUP LTD.),

                                   AS ISSUER,

                                       AND

                                  HSBC BANK USA
                    (FORMERLY KNOWN AS MARINE MIDLAND BANK),

                                   AS TRUSTEE



                          FIRST SUPPLEMENTAL INDENTURE

                          DATED AS OF FEBRUARY 4, 2000





      Supplementing the Indenture, dated as of April 30, 1998, between Bell
          Technology Group Ltd., as Issuer, and Marine Midland Bank, as
               trustee, relating to the 13% Senior Notes due 2005
                          of Bell Technology Group Ltd.





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                          FIRST SUPPLEMENTAL INDENTURE

                  FIRST SUPPLEMENTAL INDENTURE, dated as of February 4 , 2000
(this "First Supplemental Indenture"), to the Indenture, dated as of April 30,
1998 (as amended, modified or supplemented from time to time in accordance
therewith, the "Indenture"), between Globix Corporation Bell Technology Group
Ltd. (the "Company"), a Delaware corporation (formerly known as Bell Technology
Group Ltd.), and HSBC Bank USA, a New York banking corporation and trust company
(formerly known as Marine Midland Bank), as trustee (the "Trustee").

                  WHEREAS, the Company has heretofore executed and delivered to
the Trustee the Indenture providing for, among other things, the creation and
issuance by the Company of its 13% Senior Notes due 2005 (the "Securities");
and

                  WHEREAS, Section 902 of the Indenture provides that the
Company, when authorized by a resolution of its Board of Directors, and the
Trustee may amend or supplement the Indenture or the Securities without notice
to any securityholder but with the written consent of the Holders of at least a
majority in principal amount of the outstanding Securities, subject to certain
exceptions specified in Section 902 of the Indenture; and

                  WHEREAS, the Company has offered, and proposes to issue and
sell, $600,000,000 aggregate principal amount of its 12 1/2% Senior Notes due
2010 (the "New Senior Notes"); and

                  WHEREAS, in connection with the offering and proposed issuance
and sale of the New Senior Notes the Company has received the consent of the
Holders of at least a majority of the aggregate principal amount of the
outstanding Securities to the amendment of the Indenture as herein provided; and

                  WHEREAS, the execution and delivery of this First Supplemental
Indenture has been duly authorized by a resolution of the Company's Board of
Directors; and

                  WHEREAS, all conditions and requirements necessary to make
this First Supplemental Indenture a valid, binding and legal instrument
enforceable in accordance with its terms have been performed and fulfilled by
the parties hereto and the execution and delivery thereof have been in all
respects duly authorized by the parties hereto,



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                  NOW, THEREFORE, for and in consideration of the foregoing
premises, it is mutually covenanted and agreed, for the equal and proportionate
benefit of all Holders of the Securities, as follows:

                  SECTION 1. Definitions. For all purposes of the Indenture and
this First Supplemental Indenture, except as otherwise expressly provided or
unless the context otherwise requires:

                      (a) "herein," "hereof" and other words of similar import
refer to the Indenture and this First Supplemental Indenture as a whole and not
to any particular article, section or other subdivision; and

                      (b) all capitalized terms used in this First Supplemental
Indenture but not defined herein shall have the meanings assigned to such terms
in the Indenture.

                  SECTION 2. Elimination and Amendment of Certain Defined Terms
in Article 1 of the Indenture. Any defined terms appearing in Article 1 of the
Indenture or elsewhere in the Indenture, and all references thereto, that are
used solely in the sections, subsections or provisions of the Indenture deleted
from the Indenture by virtue of the operation of Sections 3, 4 and 5 of this
First Supple mental Indenture are hereby deleted in their entireties from
Section 101 of the Indenture.

                  SECTION 3. Amendment of Article 8 of the Indenture. Article 8
to the Indenture is hereby amended by deleting therefrom clauses (iii), (v) and
(vi) of Section 801(a).

                  SECTION 4. Elimination of Certain Provisions of Article 10 of
the Indenture. Sections 1008, 1009, 1010, 1011, 1013, 1015, 1016, 1017, 1018,
1019 and 1022 of the Indenture are hereby deleted in their entireties, together
with any references thereto in the Indenture.

                  SECTION 5. Operation of Supplemental Indenture. This First
Supplemental Indenture will become effective upon execution by the parties
hereto; provided however, that this First Supplemental Indenture shall be deemed
null and void as of the date hereof and shall be of no further force and effect
with respect to the Indenture, and the provisions of the Indenture modified or
eliminated by virtue of this First Supplemental Indenture shall be immediately
reinstated, if (a) on or prior to February 10, 2000 the Company does not
commence a cash tender offer to purchase any and all of the Securities at a
purchase price of 106.5% of their principal amount, plus accrued and unpaid
interest to the date of purchase (the "Tender Offer"), or if


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the Company, having commenced the Tender Offer, subsequently withdraws such
Tender Offer, or (b) if the Company, having commenced the Tender Offer, fails
to purchase, by accepting for payment, all Securities that are validly tendered
(and not withdrawn) pursuant to the terms and conditions set forth in the
Company's Offer to Purchase and the related Consent and Letter of Transmittal
prepared in connection with the Tender Offer (in each case, as the same may be
amended, modified or supplemented from time to time in accordance therewith).

                  SECTION 6. Concerning the Trustee. The Trustee accepts the
trusts of the Indenture, as supplemented by this First Supplemental Indenture,
and agrees to perform the same, but only upon the terms and conditions set forth
in the Indenture, as supplemented by this First Supplemental Indenture, to which
the parties hereto and the Holders from time to time of the Securities agree
and, except as expressly set forth in the Indenture, shall incur no liability or
responsibility in respect thereof. Without limiting the generality of the
foregoing, the recitals contained herein shall be taken as the statements of the
Company, and the Trustee assumes no responsibility for their correctness, and
the Trustee makes no representation as to the validity or sufficiency of this
First Supplemental Indenture or any consents thereto.

                  SECTION 7. Ratification and Confirmation of Indenture. Except
as expressly amended hereby, the Indenture is in all respects ratified and
confirmed and all the terms, provisions and conditions thereof shall be and
remain in full force and effect.

                  SECTION 8. Miscellaneous.

                  (a) All agreements of the Company in this First Supplemental
Indenture shall bind the Company's successors. All agreements of the Trustee in
this First Supplemental Indenture shall bind its successors.

                  (b) This First Supplemental Indenture shall be deemed to be a
contract made under the laws of the State of New York and for all purposes shall
be governed by and construed in accordance with the laws of the State of New
York.

                  (c) If and to the extent that any provision of this First
Supplemental Indenture limits, qualifies or conflicts with the duties imposed by
Sections 310-317 of the TIA by operation of Section 318(c) of the TIA, the
imposed duties shall control.

                  (d) The titles and headings of the sections of this First
Supplemental Indenture have been inserted for convenience of reference only, are
not to be consid-


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ered a part hereof and shall in no way modify or restrict any of the terms or
provisions hereof.

                  (e) This First Supplemental Indenture may be executed in any
number of counterparts, each of which so executed shall be deemed to be an
original, but such counterparts shall constitute but one and the same agreement.

                  (f) In case any provision of this First Supplemental Indenture
shall be determined to be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions hereof or of the
Indenture shall not in any way be affected or impaired thereby.

                  (g) This First Supplemental Indenture shall form a part of the
Indenture for all purposes, and every holder of Securities heretofore or
hereafter authenticated and delivered shall be bound hereby.


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                  IN WITNESS WHEREOF, the Company and the Trustee have caused
this First Supplemental Indenture to be duly executed by their respective
officers thereunto duly authorized and their respective corporate seals, duly
attested, to be hereunto affixed all as of the day and the year first above
written.

                                            GLOBIX CORPORATION,
                                                     as Issuer



[Seal]                                      By:
                                                 -------------------------------
                                                 Name:
                                                 Title:

Attest:


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                                            HSBC BANK USA,
                                                 as Trustee



[Seal]                                      By:
                                                 -------------------------------
                                                 Name:
                                                 Title:

Attest:


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STATE OF                      )
                                                 ss.:
COUNTY OF                     )

                  On the _______ day of February 2000, before me personally
came_______, to me known, who, being duly sworn, did depose and say that he is
the _________ of GLOBIX CORPORATION one of the corporations described in and
which executed the foregoing instrument; that the seal affixed to said
instrument is such corporate seal; that it was so affixed by the authority of
the Board of Directors of said corporation; and that he signed his name thereto
by like authority.


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




STATE OF          )
                                                            ss.:
COUNTY OF         )

                  On the ______ day of February 2000, before me personally came
____________, to me known, who, being duly sworn, did depose and say that he is
the _______________ of HSBC Bank USA, the banking corporation and trust company
described in and which executed the foregoing instrument; that he knows the seal
of said banking corporation and trust company; that the seal affixed to said
instrument is such banking corporation and trust company seal; that it was so
affixed by the authority of the Board of Directors of said banking corporation
and trust company; and that he signed his name thereto by like authority.


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                                            Notary Public