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                                                                    EXHIBIT 10.3

TANDBERG TELECOM AS

                                 PROMISSORY NOTE
                                    (Secured)

US$ 1,250,000.00                                Burlington, MA
                                                August 1, 2002

          FOR VALUE RECEIVED, the undersigned, EZENIA! INC. (hereinafter
referred to as the "Borrower"), unconditionally promises to pay to TANDBERG
TELECOM AS (hereinafter referred to as the "Lender") or order at its offices
located at Philip Pedersen's Vei 22, N-1324, Lysaker, Norway, the principal sum
of ONE MILLION TWO HUNDRED AND FIFTY THOUSAND UNITED STATES DOLLARS (US$
1,250,000.00), together with interest in arrears on the unpaid principal balance
from time to time outstanding from the date hereof until the entire principal
amount due hereunder is paid in full at the rate hereinafter provided.

          Payment of the outstanding balance hereunder shall be made as follows:
All amounts unpaid under the terms of this Note shall be paid no later than
October 31, 2002 (the "Due Date"). Interest shall be payable at the annual rate
of seven and one-half (7.5%) percent; provided, however, that in the event that
any payment due hereunder is not paid on the Due Date, interest shall accrue on
the outstanding balance at the rate of eighteen percent (18%) per annum in
addition to such other charges as may be incurred. To secure the payment,
promptly when due, of all the Liabilities as hereinafter defined, Borrower
hereby pledges, assigns, and grants to Lender a first priority lien upon and
security interest in, all of the Collateral as hereinafter defined.

          The Borrower represents that the pledge herein of security to Lender
and the execution of this Note and all the terms hereof have been duly
authorized by the Borrower. The Borrower agrees to execute upon demand all
appropriate documents necessary to perfect the security interest granted herein.

               a.   "Collateral" means any and all of the following whether now
owned or hereafter acquired and related in any way to the business of the
Borrower: (i) the Purchased Assets (as defined in the Asset Purchase Agreement,
dated as of the date hereof, between the Borrower and the Lender) and (ii) all
Proceeds of the foregoing.

               b.   "Proceeds" means whatever is received when Collateral is
sold, exchanged, presented, collected, drawn upon or otherwise disposed of.

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          The occurrence of any of the following events shall constitute an
Event of Default under this Note: (i) the failure to make any payment, whether
principal, interest or other payment, under any of the undersigned's Liabilities
when the same is due, (ii) the dissolution, suspension of business for any
reason or insolvency (however such insolvency may be evidenced) of any Obligor
hereunder, (iii) the assignment by any Obligor hereunder for the benefit of
creditors, or the admission in writing of its inability to pay its debts as they
become due or the filing of a voluntary petition in bankruptcy, or the filing of
any petition or answer seeking any reorganization, arrangement, composition,
adjustment, liquidation, dissolution or similar relief under the Federal
Bankruptcy Code or any future Federal bankruptcy act or other applicable
Federal, state or other statute, law or regulation, or seeking or consent into
or acquiescing in the appointment of any trustee, custodial, receiver or
liquidator or similar official of any Obligor hereunder or all or any
substantial part of its properties, or taking any action for the purpose of
effecting any of the foregoing, (iv) any Obligor hereunder shall be the subject
of an order for relief in an involuntary case under the Federal Bankruptcy Code
or any petition or proceeding against any Obligor hereunder seeking any
reorganization, arrangement, composition, adjustment, liquidation, dissolution
or similar relief under the Federal Bankruptcy Code or any future Federal
Bankruptcy act or other applicable Federal, state or other statute, law or
regulation shall be commenced, or any trustee, custodian, receiver or liquidator
or similar official of any Obligor hereunder or all or any substantial part of
its properties, shall be appointed without the consent or acquiescence of such
Obligor, (v) the sale, lease or other disposition, or attempted disposition, of
all or a substantial part of the stock, membership interests, partnership
interests, assets or property of any Obligor hereunder, (vi) the issuance of a
writ, warrant, distraint or order of attachment or garnishment against any of
the property or assets of any Obligor, (vii) the commencement of foreclosure
proceedings or any proceedings for the enforcement of money judgments against
any Obligor hereunder, (viii) the seizure, nationalization, condemnation or
other assumption by any government or political subdivision thereof of a
substantial part of the business or property of any Obligor hereunder, (ix) the
occurrence of an event of default as described and defined in any instrument
securing the obligations hereunder or any instrument evidencing any indebtedness
of the undersigned to the Lender and the expiration of any period provided in
such instrument to cure such default or (x) any breach by Obligor of the License
Agreement or Asset Purchase Agreement executed concurrently herewith by the
parties hereto, and the expiration of any period provided in such agreement to
cure such default.

          Upon the happening of any Event of Default, the holder hereof may
declare the entire unpaid principal balance under this Note and under any and
all other liabilities of the undersigned to the holder hereof immediately due
and payable without notice, demand or presentment and may exercise any of its
rights under any instruments security the obligations hereunder. In the event
that the Lender or any subsequent holder of this Note shall exercise or endeavor
to exercise any of its remedies hereunder or under any instruments securing the
obligations hereunder, the undersigned shall pay on demand all reasonable costs
and expenses incurred in connection therewith, including, without limitation,
reasonable attorney's fees, and the Lender may take judgment for all such
amounts in addition to all other sums due hereunder.

          The undersigned waives presentment for payment, protest and demand,
and notice

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of protest, demand and/or dishonor and the payment of this Note, notice of any
event default under any instrument securing the obligation hereunder, except as
specifically provided herein, and all other notices or demands otherwise
required by law that the undersigned may lawfully waive. Each Obligor expressly
agrees that this Note, or any payment hereunder, may be extended from time to
time, without in any way affecting the liability of the Obligor. No unilateral
consent or waiver by the Lender with respect to any action or failure to act
which, without consent, would constitute a breach of any provision of this Note
shall be valid and finding unless in writing and signed by the Lender.

          The rights and obligations of the undersigned and all provisions
hereof shall be governed by and construed in accordance with the laws of the
State of Delaware, exclusive of its conflicts of law principles.

          This Note and the transactions contemplated hereby constitute
commercial activities of the undersigned. The undersigned is not entitled to any
immunity, whether characterized as sovereign immunity or otherwise, from any
legal proceedings. The undersigned, in respect of its obligation under this
Note, expressly and irrevocably waives such immunity in any action or proceeding
and hereby irrevocably agrees that the legal action proceeding arises out of or
relating to this Note or the transaction contemplated hereby may be brought in
the Chancery Court of the State of Delaware or of the United States of America
for the District of Delaware. The undersigned hereby expressly submits to the
jurisdiction of such courts and irrevocably waives to the full extent permitted
by law and any objection it may now hereafter have based upon improper venue or
forum non conveniens with respect to such action or proceeding in such courts,
and waives the benefit of any other jurisdiction to which it may entitled by
reason of present or future domicile or otherwise. The undersigned further
irrevocably consents to the service of process out of the aforementioned Courts
in any said action or proceeding by the mailing of the copies thereof by
certified mail, postage prepaid, to it at its address set forth below, such
service to become effective upon the earlier of (i) the date fifteen (15) days
after such mailing or (ii) in the earlier date permitted by applicable law.
Nothing herein shall affect the right of the Lender to commence legal
proceedings or otherwise proceed against the undersigned in the state of its
citizenship or organization or in any other competent jurisdiction where the
undersigned has assets or to serve process in any other matter permitted by
applicable law.

          If this Note is signed by more than one maker, the liability of each
shall be joint and several. THE UNDERSIGNED HEREBY WAIVES TRIAL BY JURY AND THE
RIGHT TO INTERPOSE ANY COUNTERCLAIM OR OFFSET OF ANY NATURE OR DESCRIPTION IN
ANY LITIGATION RELATING TO THIS NOTE OR ANY LIABILITY HEREUNDER OR ENFORCEMENT
OF REMEDIES HEREUNDER TO THE FULLEST EXTENT PERMITTED BY LAW. Any provision of
this Note which is prohibited or unenforceable in any jurisdiction shall, as to
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof or
affecting the validity or enforceability of such provision in any other
jurisdiction.

          As used herein, the terms, "the undersigned" shall mean the
undersigned or any one or more of them; "Liabilities" shall mean any and all
debts and obligations of the

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undersigned owed to the Lender pursuant to this Promissory Note, whether such
shall be primary, direct, contingent, sole, joint or severally, due or to become
due, or that have or may hereafter be contracted or incurred; and "Obligor"
shall mean each of the undersigned and any co-signer, endorsed, guarantor or
surety of or for the undersigned's Liabilities.

     IN WITNESS WHEREOF, the undersigned has caused this Note to be duly
executed as of the day and year first above written.


Address:                          EZENIA! INC., Borrower


154 Middlesex Turnpike            By:  /s/ Khoa D. Nguyen
Burlington, MA 01803                   -----------------------------------------
President                                     Khoa Nguyen, its duly authorized