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                              CONSULTANT AGREEMENT
                              --------------------

     This Agreement dated as of November 1, 1999 is made between PacketPort,
Inc., a Delaware corporation, with offices presently located at 587 Connecticut
Avenue, Norwalk, Connecticut 06854, hereinafter referred to as "PacketPort" or
"The Company," and Thomas Cerabona, whose address is 3061 Dahlia Court, Yorktown
Heights, New York 10598, hereinafter referred to as "cerabona" or "the
consultant."

                               W I T N E S S E T H

     WHEREAS, PacketPort is acquiring a substantial stockholder interest in the
company known as Linkon Corporation, hereinafter referred to as "Linkon" and
will be advancing funds to Linkon to pay certain of its creditors on a
compromised basis;

     WHEREAS, the Consultant was formerly employed by Linkon, was the recipient
of rights in the form of warrants and/or options to purchase securities issued
by Linkon; and may be owed compensation for services rendered to Linkon;

     WHEREAS, PacketPort desires to utilize the services of Cerabona in the
capacity of a consultant to the Company for a period of at least one year
provided he releases all other claims against linkon for compensation in any
form;

     WHEREAS, the Consultant has agreed to be retained by PacketPort for the
purpose of providing consulting services related to his knowledge of the
business and technology of Linkon;

     NOW, THEREFORE, in consideration of the mutual covenants, promises and
agreements set forth in this Consultant Agreement, the parties agree as follows:


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     19.  Incorporation of "WHEREAS" clauses. The representations, terms and
undertakings set forth in the WHEREAS clauses of this Agreement are incorporated
herein by reference as though recited verbatim and at length.

     20.  CONSULTATION SERVICES. The Company hereby employs the Consultant to
perform the following services in accordance with the terms and conditions set
forth in this agreement:

     21.  TERM OF AGREEMENT. The term of this Agreement will commence November
1, 1999 and will end October 31, 2000.

     22.  TIME DEVOTED BY CONSULTANT. It is anticipated that Cerabona will not
perform services on a regular basis but only from time to time in order to
fulfill his obligation under this Agreement. The particular amount of time in
which the services are rendered should be at the convenience of the Consultant.

     23.  PLACE WHERE SERVICES WILL BE RENDERED. Cerabona will perform the
services contemplated by this Agreement at the offices of PacketPort or at his
own office wherever it may be more convenient for him.

     24.  COMPENSATION PAID TO CONSULTANT. Cerabona will be paid the sum of
$50,000 as a retainer fee for entering into this one year term agreement.
Payment of the consulting fee will be as follows: $26,000 upon execution of this
Agreement and six month payments thereafter of $4,000 each. In the event the
Consultant incurs expenses, he should submit an itemized statement setting forth
the expenses incurred and the Company will pay the Consultant the amounts due as
indicated by statements submitted by the Cerabona on a month to month basis.

     25.  INDEPENDENT CONTRACTOR. The parties agree that Cerabona will act as an
independent contractor in the performance of his duties under this Agreement.
Accordingly, the Consultant shall be responsible for payment of all

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payroll taxes, including federal, state and local taxes, arising out of the
Consultant's activities in accordance with this Agreement.

     26.  CONFIDENTIAL INFORMATION. Cerabona agrees that any information
received by him during the course of carrying out the terms and conditions of
this Agreement which concerns the personal, financial or other affairs of the
Company will be treated by the Consultant in full confidence and will not be
revealed to any other person, firm or organization.

     27.  EMPLOYMENT OF OTHERS. The Company may from time to time request that
Cerabona arrange for the services of others. All expenses incurred to the
Consultant for those services will be paid by the Company but in no event shall
the Consultant employ other persons without the prior authorization of
management.

     28.  CONTINUANCE OF DIRECTORS AND OFFICERS INSURANCE COVERAGE.
PacketPort agrees that, if it is contractually possible to do so, it shall take
such steps as would be necessary and appropriate to continue the current D&O
insurance policy in favor of the previous directors and officers of Linkon for
the twelve month term of this Agreement.

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     29.  GENERAL RELEASE. In exchange for the compensation to be received by
the Consultant, Cerabona agrees to deliver to the Company a general release
executed by him and acknowledged in the form attached as Exhibit "A" to this
Agreement.

     30.  MISCELLANEOUS. This Agreement constitutes the entire Agreement between
the parties. No other statement, representation, warranty or covenant has been
made by either party with respect to the Consultant.

     31.  INDEMNIFICATION. PacketPort agrees that it will indemnify and hold
harmless Cerabona from and against any and all losses, claims, damages,
liabilities and expenses, joint or several (including all reasonable fees of
counsel and other expenses incurred by him in connection with the preparation
for, or defense of, any claim, action or proceeding, whether or not resulting in
any liability), to which such Consultant may become subject under any applicable
federal or state law, or otherwise, caused by or arising out of any action or
failure to take action by the Company and/or Linkon, except that the Company
will not be liable hereunder to the extent that any loss, claim, damage,
liability or expense is found to have resulted from gross negligence or bad
faith on the part of Cerabona. PacketPort also agrees that it will cause the
Board of Directors of Linkon to authorize a similar indemnification provision in
favor of the Consultant.

     32.  AMENDMENTS. No amendments or modifications of the terms and conditions
of this Agreement shall be valid and enforceable unless set forth in writing.

     33.  SEVERABILITY. In the event that any provision of this Agreement is
held invalid, unenforceable or modified by any court of competent jurisdiction,

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it shall be construed as if such invalid, unenforceable or modified provision
had been more narrowly drawn so as not to invalidate or make unenforceable or
modify any other provision.

     34.  GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of Connecticut without regard to conflict
of laws principles.

     35.  CONSULTATION WITH COUNSEL. The Consultant acknowledges that prior to
executing this Agreement he has had the opportunity to consult with independent
counsel of his personal choice.

     36.  NO RIGHT TO ASSIGN AGREEMENT. The Consultant may not assign, transfer,
pledge, encumber, hypothecate or otherwise dispose of this Agreement. Any
attempted delegation or disposition of any of this rights under this Agreement
shall be null and void and without effect.

     IN WITNESS WHEREOF, this Consultant Agreement has been executed by the
parties hereto the date first above written.


Witnessed or Attested by:           PACKETPORT, INC.


__________________________          ____________________________
Robert H. Jaffe, Secretary          Ronald A. Durando, President

                                  ______________________________
                                  Thomas V. Cerabona, Consultant
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