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                                                                    Exhibit 10.9

                                NX NETWORKS, INC.
                              CONSULTING AGREEMENT

Agreement  ("Agreement") dated this 1st day of December,  2000 by and between Nx
Networks,  Inc., a Delaware corporation doing business as Nx Networks and having
its principal office located at 13595 Dulles Technology Drive, Herndon, VA 22071
("Nx  Networks")  and Keir  Kleinknecht,  an individual  residing at the address
below his signature  ("Consultant").  Nx Networks and  Consultant  are sometimes
referred to hereinafter singly as "party" and collectively as "parties."

1.      TERM.  Subject  to the terms of this  Agreement,  the term of this
Agreement  shall commence on the date specified  above and continue for a period
of two (2) years,  provided  that unless  either party gives the other notice of
termination  not later than 15 days  before the  scheduled  termination  of this
Agreement,  the term shall continue for successive thirty (30) day periods until
either  party  terminates  this  Agreement  upon thrity (30) days prior  written
notice.

2.      CONSULTING SERVICES. Consultant agrees to perform such consulting
services  as are  requested  of him  from  time to time by the  Chief  Executive
Officer  of Nx  Networks.  The  time and  location  of  performance  shall be as
mutually  agreed  between  Consultant  and the  Chief  Executive  Officer  of Nx
Networks.

3.      COMPENSATION.

        a)   RETAINER. Nx Networks shall pay to Consultant a retainer of $15,000
per  calendar  month  during the term of this  Agreement,  prorated  for partial
months, which amount shall be payable within ten (10) days after the end of each
month.

        b)   WARRANTS.  Nx Networks  shall grant to  Consultant  warrants to
acquire  common stock of Nx Networks.  The exercise  price of all such  warrants
shall be $0.70 per share,  and shall  have a term of five  years.  The  warrants
shall be granted as follows:

           o   240,000 warrants upon execution of this Agreement, for  services
               pursuant to this Agreement;
           o   100,000  warrants upon  execution of this Agreement, which will
               only vest if a new chief executive officer joins Nx Networks on
               or before January 15, 2001; and

           o   160,000  warrants upon  execution of this  Agreement,  which will
               only vest if a financing for at least $5 million is secured on or
               before February 15, 2001.

4.    NON-EXCLUSIVE  AGREEMENT.  Nx Networks and Consultant do not intend that
any  exclusive  relationship  be  created  between  them.  Each party is free to
independently pursue similar business opportunities.

5     CANCELLATION  OF  SERVICES.  Either  party has the  option of  canceling
this  Agreement  at any  time,  effective  upon  notice  to the  other of such
termination.

6.     ASSIGNMENT.  Consultant hereby agrees that all work provided hereunder
shall be considered  "work for hire" and that Netrix shall own all  intellectual
property rights to the deliverables  described in Appendix A. Consultant  agrees
to complete any necessary paperwork, including but not limited to the execution

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of a formal  Assignment  Agreement in order to perfect Netrix' interests in such
intellectual property rights.

7.      NOTICES.  All notices required hereunder shall be given in writing to
the address  listed  above,  either by personal  delivery,  by first class mail,
return receipt requested, or by telex or facsimile. The date upon which any such
notice  is so  personally  delivered,  or the date  three  (3) days  after it is
deposited in the mail, or the date the telex or fax is sent,  shall be deemed to
be the date of notice irrespective of the date appearing therein.

8.      INDEPENDENT  CONTRACTORS.  The  relationship  of Nx Networks and
Consultant established by this Agreement is that of independent  contractors and
nothing  contained herein shall be construed to: (i) give either party the power
to direct and control the day-to-day  activities of the other;  (ii)  constitute
the parties as partners, joint venturers, co-owners or otherwise as participants
in a joint or  common  undertaking;  or (iii)  allow  either  party to create or
assume any obligation on behalf of the other for any purpose whatsoever.

9.     ASSIGNMENT.  Any  assignment by Consultant of this  Agreement or any of
its rights or  obligations  hereunder,  either  voluntarily or by operation of
law shall be void without prior written consent of Nx Networks.

10.    SURVIVAL OF  OBLIGATIONS.  All  obligations of either party which, by
their nature,  require  performance  after the expiration or termination of this
Agreement,  shall survive the  expiration or  termination  of this Agreement and
continue to be enforceable.

11.    GOVERNING  LAW.  This  Agreement  shall be governed by and  construed in
accordance with the laws of the Commonwealth of Virginia.

12.   PUBLICITY. Neither party shall have the right to include the other party's
name in  marketing  and other  materials  or to disclose  and/or  summarize  the
general nature of this Agreement  except to comply with  employment laws or when
requested to do so in writing by the other party.

13.   ENTIRE AGREEMENT.  This Agreement together with the Appendices  attached
hereto, constitutes the entire Agreement between the parties.


Executed as of the date first above written.

NX NETWORKS, INC.                   Keir Kleinknecht

By:___________________                    Signature:____________________

Title:__________________                  Address: 242 East 48th Street
                                                   New York, NY 10017






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