LICENSE AGREEMENT

                                     Between

                         Vistar Telecommunications Inc.
                       Suite 1410, 427 Laurier Avenue West
                        Ottawa, Ontario, Canada, K1G 3J4
                      (hereinafter referred to as "Vistar")

                                       And

                          Comtech Mobile Datacom Corp.
                        19540 Amaranth Dr. P.O. Box 2126
                      Germantown, Maryland, USA, 20875-2126
                       (hereinafter referred to as "CMDC")

WHEREAS,  Vistar and CMDC  entered into a  Memorandum  of Agreement  (MOA) dated
December 12, 1997 intending to pursue  opportunities  related to the development
and supply of mobile satellite  terminals for use on domestic and  international
satellite  systems and having  identified an opportunity  with the United States
Department  of Defense  under the  Commercial  Operations  and  Support  Savings
Initiative (the "Project");

WHEREAS,  Vistar intended to provide  engineering  capabilities  with respect to
designing and prototyping mobile satellite terminals;

WHEREAS,  CMDC  intended to provide  engineering  capabilities  with  respect to
designing and producing satellite access and control equipment and is a supplier
of mobile satellite equipment to the American Government and commercial users;

WHEREAS,  pursuant  to the  said  MOA  the  Parties  intended  to  enter  into a
Development and Supply Contract (DSC) within 90 days;

WHEREAS, the Parties commenced  performance of their respective  obligations but
failed to enter into a DSC;

WHEREAS,  CMDC is now desirous of licensing  certain  Vistar  Technology for the
purpose of continuing with the Project,  including the development and marketing
of Mobile Satellite Terminals;

WHEREAS,  Vistar is desirous of granting CMDC certain  rights to license its MST
Technology;

NOW THEREFORE, in mutual consideration,  the payment and sufficiency of which is
hereby expressly  acknowledged by both Vistar and CMDC, the Parties hereby agree
as follows:


                                      1





1.    DEFINITIONS

Defined terms used in this License  Agreement  shall have the meanings set forth
below:

     1.1  "Background  Technology"  shall mean all technology  incorporated into
          the MST that is not first conceived,  developed or reduced to practice
          as part of the activities  carried out by the Parties  pursuant to the
          terms  of  this  Agreement  and/or  the  MOA.  Background   Technology
          includes,  without limitation,  any hardware and software designs that
          come with  Vistar to this  Agreement  and are  proprietary  to, or the
          Confidential  Information of Vistar,  its  subcontractors or any other
          supplier of Vistar.

     1.2  "CECOM" shall mean the United States Army Communications - Electronics
          Command.

     1.3  "Confidential  Information" or "Information"  shall mean all materials
          relating  to the  business  or  affairs of either  Party  whether of a
          financial,  technical operation or economic nature including,  without
          limitation,  MTS Technology,  Background  Technology,  all unpublished
          know-how,  technical data, techniques,  records, formulae,  processes,
          designs,  sketches,  photographs,  plans,  drawings,   specifications,
          samples, reports, studies, manuals,  documents,  prototypes,  business
          plans,  equipment,  working materials,  lists of customers,  findings,
          inventions and ideas whether  patentable or not, whether they be trade
          secrets  or not and  whether  they be in  written,  machine  readable,
          graphic or oral form,  that are now or hereafter  owned or acquired by
          the  Disclosing  Party and  disclosed to the  Receiving  Party.  It is
          expressly  understood that Confidential  Information shall include all
          copies and/or reproductions made by the Receiving Party of Information
          originally   provided  under  this  License  Agreement  and  that  all
          Confidential Information shall at all times remain the property of the
          Disclosing   Party.   Confidential   Information   does  not   include
          information  which the Receiving Party can clearly  demonstrate to the
          satisfaction of the Disclosing Party:

          (i)  is at the time of disclosure,  or thereafter  becomes,  a part of
               the public domain through no act or error by the Receiving Party;
               or
          (ii) was in  the  lawful  possession  of the  Receiving  Party  before
               disclosure by the Disclosing Party as shown by competent  written
               evidence and was not already subject to an agreement  between the
               Parties  restricting  the  disclosure  of the  said  Confidential
               Information; or
          (iii)is  developed  independently  by the  Receiving  Party  prior  to
               receipt of the Information from the Disclosing Party, as shown by
               competent  written  evidence;  or
          (iv) is  required  to be  released  under  court  order or  government
               regulation,  provided  that, to the extent  permitted by law, the
               Disclosing  Party is promptly  given a copy of such order and the
               Receiving  Party  co-operates  with the  Disclosing  Party if the
               Disclosing   Party  elects  to  dispute  such   requirement   for
               disclosure.

                                      2






     1.4  "Deliverables" shall mean the items including, without limitation, the
          Technology  stipulated  in  Schedules  A and B that one  Party to this
          Agreement is obligated to provide to the other.

     1.5  "Disclosing  Party"  shall  mean  the  Party  to this  Agreement  that
          discloses Confidential Information to the Receiving Party.

     1.6  "Dispute" shall mean any  disagreement  or dispute arising under,  out
          of, in connection  with or relating to the intent or operation of this
          License Agreement.

     1.7  "Effective Date" shall mean the date upon which this License Agreement
          becomes  effective,  which  shall  be  deemed  by  the  Parties  to be
          _________________ .

     1.8  "Intellectual  Property" shall mean all forms of intellectual property
          pertaining to the subject  matter of this License  Agreement,  and may
          include,  without limitation,  all right, title and interest in and to
          all:

          (i)  issued patents and all filed or pending applications for patents,
               including any  continuations,  continuations in part,  re-issues,
               re-examinations,  substitutions  and extensions  thereof,  in any
               country or other  jurisdiction in the world;  (ii) trade secrets,
               and all trade secret rights and  equivalent  rights arising under
               the common law, state law,  Federal law,  Provincial law and laws
               of  foreign  countries;  (iii)  mask  works,  copyrights,   other
               literary property or authors' rights, whether or not protected by
               copyright or as a mask work, under common law, state law, Federal
               law,   Provincial  law  and  laws  of  foreign  countries;   (iv)
               proprietary  indicia,  trademarks,  trade names,  symbols,  logos
               and/or  brand names under  common law,  state law,  Federal  law,
               Provincial  law and  laws of  foreign  countries;  and (v)  other
               Confidential Information.

     1.9  "Intellectual  Property  Rights" shall mean all forms of  intellectual
          property rights and protection in any country or other jurisdiction of
          the  world  that may be  obtained  for,  or  pertain  to  Intellectual
          Property.

                                      3





     1.10 "License" shall mean the license,  granted by Vistar to CMDC,  subject
          to the terms and  conditions  of this  Agreement,  including,  without
          limitation, those set out in Section 3.

     1.11 "License  Agreement" or "Agreement" shall mean this legal document and
          the Schedules  hereto,  containing  the rights and  obligations of the
          Parties,  including,   without  limitation,   those  relating  to  the
          Deliverables  and the licensing by Vistar to CMDC of certain rights in
          the MST Technology.

     1.12 "Marks" shall mean all trademarks,  trade names, symbols, brand names,
          logos and other proprietary  indicia wherein a Party to this Agreement
          has a right, title or interest.

     1.13 "Material Breach" unless otherwise stated, shall mean a failure by one
          Party to perform a material covenant,  condition or obligation of this
          Agreement.

     1.14 "Mobile Satellite  Terminal" or "MST" shall mean a terminal containing
          MST Technology.

     1.15 "Mobile   Satellite   Terminal   Technology",   "MST   Technology"  or
          "Technology"  shall  mean  the  Vistar  proprietary   terminal  design
          contained  within the Vistar  Deliverables  including all Intellectual
          Property Rights therein licensed to CMDC pursuant to the terms of this
          Agreement.

     1.16 "Receiving Party" shall mean the Party to this Agreement that receives
          Confidential Information from the Disclosing Party.

     1.17 "Royalty"  or  "Royalties"  shall  mean  the  payments  which  CMDC is
          obligated to pay Vistar in accordance with the terms of Section 3.3 of
          this Agreement.

     1.18 "Specifications" shall mean the MTS system and terminal specifications
          attached hereto as Schedule C.

     1.19 "Term"  shall have the meaning set forth in Section 5 of this  License
          Agreement.



                                      4





2.    DELIVERABLES

      2.1   Vistar Deliverables.

      Vistar  hereby  agrees to provide to CMDC the  Deliverables  in accordance
      with the terms of Schedule A. Upon  CMDC's  receipt of such  Deliverables,
      and upon Vistar's  receipt of payment for such  Deliverables in accordance
      with the terms of  Section  4,  Vistar  agrees to grant  CMDC the  License
      described in Section 3.

      2.2   CMDC Deliverables.

      CMDC  hereby  agrees to  provide  to Vistar  the  Deliverables  set out in
      Schedule B. It is  expressly  understood  that Vistar  requires  such CMDC
      Deliverables inasmuch as the said CMDC Deliverables are required by Vistar
      in order  for it to  commence  and/or  continue  performance  of  Vistar's
      obligations.  Such CMDC  Deliverables,  including  but not  limited to PCB
      boards,   enclosures,   components  and  connectors  associated  with  the
      prototype  Rev D units shall be  manufactured,  provided and  assembled in
      accordance with the requirements set out in the Vistar Deliverables.

      2.3   Inventory in Stock.

      Vistar agrees to provide to CMDC, in a timely manner,  for use by CMDC and
      or its  manufacturer,  any  inventory  held by Vistar  on May 14,  1999 of
      applicable parts for up to six (6) prototype boards.

      2.4   CMDC Indemnification.

      Any  costs  incurred  by CMDC  and/or  its  manufacturer  relating  to the
      obligations of this Section are the responsibility of CMDC. Subject to the
      terms of this Agreement,  including,  without limitation,  Section 7, CMDC
      assumes  liability  associated  with the  obligations  of CMDC  under this
      Section and indemnifies  Vistar for any losses and/or damages  incurred by
      Vistar in connection with CMDC's failure to perform its obligations  under
      this Section.

      2.5   Vistar Indemnification.

      Subject  to the terms of this  Agreement,  including  without  limitation,
      Section 7, Vistar assumes  liability  associated  with the  obligations of
      Vistar under this  Section 2 and  indemnifies  CMDC for any losses  and/or
      damages  incurred by CMDC in connection  with Vistar's  failure to perform
      its obligations under this Section.

                                      5





3.    LICENSE AND ROYALTIES

      3.1   No Transfer of Technology.

      Except as expressly  set out in this Section 3, this  Agreement  shall not
      result in a conveyance, transfer of title, license, or grant of any rights
      in any technology or Intellectual Property of one Party to another.

      3.2   Mobile Satellite Terminal License.

      In consideration of CMDC's obligations under this Agreement, Vistar hereby
      grants to CMDC during the Term of this Agreement only:

          (i)  a  non-exclusive,   non-transferable   license  to  use,  modify,
               maintain, lease or sell Mobile Satellite Terminals containing MST
               Technology;
          (ii) subject to the provisions of Subsection 3.2(iv), a non-exclusive,
               non-transferable  license to  provide,  to the MST  manufacturers
               selected  by  CMDC,  the MST  Technology  excluding  Source  Code
               required  by  such   manufacturers   for  the  sole   purpose  of
               manufacturing MSTs. However,  the Parties expressly agree that in
               the event the manufacturer selected by CMDC is not located in the
               United  States or  Canada,  CMDC must  obtain  the prior  written
               consent  of  Vistar,  which  consent  shall  not be  unreasonably
               withheld, for release of MST Technology to the Manufacturer;
          (iii)notwithstanding   Subsection   3.2(i)   above,   subject  to  the
               requirement  to obtain  Vistar's  prior  written  consent in each
               case,  which  consent  shall not be  unreasonably  withheld,  and
               subject to the terms of  Subsection  3.2(iv) as well as any other
               commercially reasonable terms stipulated by Vistar, Vistar agrees
               to grant CMDC the right to sub-license MST Technology,  on a case
               by case basis, to third parties.  The Parties hereby  acknowledge
               that such  commercial  terms may,  in Vistar's  sole  discretion,
               include  amendments to, or replacements  of, the terms respecting
               Royalties.  In such an event, the Parties agree, for the purposes
               of only the specific  sub-license under  consideration,  to enter
               into a written agreement  reflecting any such amendments.  In the
               event that  Vistar  grants its  consent  to a  sub-license  it is
               expressly  understood  that  CMDC  remains  responsible  for  the
               payment  to  Vistar  of  all  Royalties   associated   with  MSTs
               sub-licensed  in  accordance  with the  terms of this  Subsection
               3.2(iii)  and/or for any other payments due to Vistar pursuant to
               the said modifications to the Royalty terms;
          iv)  In the event that MST  Technology,  or part thereof is authorized
               by Vistar for release to a third party  manufacturer  pursuant to
               Subsection  3.2(ii) above,  or the granting of a sub-license to a
               third  party is  authorized  by  Vistar  pursuant  to  Subsection
               3.2(iii) then as a pre-condition to the said authorization coming
               into effect, CMDC must enter into (i) a sub-license agreement, in
               a form satisfactory to Vistar,  with such third party stipulating
               the terms of the

                                      6





               sub-license; and (ii) a Confidentiality Agreement in the form set
               out in Schedule D with such third  party and Vistar.  CMDC hereby
               agrees  to  indemnify   Vistar  for  all  losses  and/or  damages
               including,  without  limitation,  legal fees,  resulting from the
               breach of such agreement by such third party.

      3.3   Royalties.

          (i)  CMDC will also pay to VISTAR, upon successful production and sale
               of Mobile Satellite  Terminals,  a Royalty calculated at the rate
               of XX dollars  ($XX) per MST for up to and including
               each of the first ten thousand  (10,000)  terminals  produced and
               sold, and XX dollars  ($XX) per terminal for each and every
               terminal produced and sold thereafter.

          (ii) Unless the Term of this Agreement is extended pursuant to Section
               6.2,  the Royalty  shall be payable for a period of six (6) years
               commencing on the production of the first  commercial MST. In the
               event that the Term of the  Agreement  is  extended  pursuant  to
               Section  6.2 then the  Royalty  shall  continue  to be payable to
               Vistar for an additional  period  equivalent to the length of the
               extension to the Term. It is expressly  agreed that in accordance
               with this methodology,  CMDC's  obligations to pay Royalties will
               continue after the expiration of the Term of the Agreement  until
               the   expiration  of  the  periods  of  time  described  in  this
               Subsection.

          (iii)Royalties  shall be paid on a quarterly  basis with the  payments
               reflecting the Royalties  associated  with MSTs produced and sold
               during the immediately  preceding quarter. A report detailing the
               Royalty  calculation shall be provided with each Royalty payment.
               On an annual  basis,  at Vistar's  option,  Vistar can request an
               audit of the Royalty  calculation.  The audit will be at Vistar's
               expense  unless it is  determined  through  the  audit  that CMDC
               failed to pay any Royalties owing to Vistar under this Agreement,
               exceeding five percent (5%) of the Royalty amount paid by CMDC in
               which case, CMDC shall bear all costs of the audit.


                                      7







4.    MILESTONE AND PAYMENT

      4.1   Vistar Schedule of Milestones and Corresponding CMDC Payments.


                                                                   Milestone
      Milestone Date              Milestone Description              Amount
- -------------------------- ------------------------------------ ----------------
WEEK 2 Letter of Intent May 14, 1999 Rev C Documentation Package:
                           o     Softcopy Schematic
                           o     Softcopy (Board) Layout                $XX
                           o     Softcopy Mechanical Drawing
                                 of Enclosure
                           o     Bill of Materials (Costed)
                           o     Specifications for Custom
                           o     Order Parts (Hardcopy)
                           o     Test Proecedure (Softcopy)
                           o     Softcopy (or hardcopy)
                                 mechanical drawing of antenna
- -------------------------- ------------------------------------ ----------------
WEEK 14, AUG. 9, 1999      Execution of Transfer of Licensing           $XX
                           Agreement
WEEK 8, 6/25/99            Rev D Schematic and
WEEK 10, 7/13/99           BOM (Prototype Build)
WEEK 11, 7/23/99                   Rev D Layout Sent for Board Build    $XX
WEEK 17, 8/26/99                   Start  of Rev D Test                 $XX
WEEK 11, 7/23/99           Rev D  Enclosure  Drawings                   $XX
WEEKS 17-23
8/26-10/7                          Rev D Test
WEEK 24, 10/14             Deliver Rev D Hardware-Golden Boards
                           Deliver Rev D Documentation
WEEK 25, 10/21             Deliver Rev D Software                       $XX
                           Deliver Test Equipment (Item 2),
                           OS License (Item 4)
COMPLETION                 TOTAL                                        $XX
- -------------------------- ------------------------------------ ----------------



                                      8





      4.2   Payment Terms.

      Subject to the terms of this Agreement,  CMDC shall pay, and VISTAR agrees
      to accept the sum of XX dollars  ($XX)
      in  satisfaction  of its obligation to provide  Deliverables in accordance
      with  this   Agreement.   The  Parties   agree  that  payment  for  Vistar
      Deliverables shall be made in accordance with the above Mileston Schedule.
      Vistar shall invoice CMDC immediately upon completion of a Milestone.  All
      Milestone payments shall be paid by CMDC net thirty (30) days from receipt
      of an invoice.

      4.3   CMDC Schedule of Milestones.


         Milestone Date                  Milestone Description
- ------------------------------------------------------------------------
8/26/99                         Two Prototype Rev D Boards ready for Test

9/2/99                           Two Sets of Test Housings


5.    TAXES

Except for taxes on the income of Vistar,  CMDC shall be responsible for any and
all taxes of whatever nature due or arising under or out of this Agreement.  All
rates and/or prices set forth in Subsections  3.3,  4.1(i),  15.19 and 15.20 are
exclusive  of any and all  taxes,  levies,  assessments,  surcharges,  duties or
similar  items  assessed  by a  government  body,  and CMDC  shall be solely and
exclusively  responsible for collection,  remittance  and/or compliance with any
such taxes.

6.    TERM

      6.1   Initial Term.

      This License  Agreement  shall come into force on the  Effective  Date and
      shall  remain in effect for a period of six (6) years from the  production
      of the  first  commercial  MST  or,  in  the  event  that  CMDC  fails  to
      commercially produce MSTs, eighteen (18) months from the Effective Date.

      6.2   Extension to Initial Term.

      At CMDC's option,  and subject to CMDC's obligations in Subsection 3.3(ii)
      the Term may be extended for four (4) subsequent one year periods.  In the
      event that CMDC  wishes to  exercise  an option to extend the Term of this
      Agreement,  then  prior  to the  expiration  of the  current  Term it must
      provide  Vistar with no less than sixty (60) days prior written  notice of
      its  intent  to  extend  the  Term.  In no  event  shall  the Term of this
      Agreement exceed ten (10) years.

                                      9





7.    LIABILITY

      7.1   LIMITATION OF LIABILITY.

      IN NO EVENT SHALL  EITHER  PARTY BE LIABLE TO THE OTHER PARTY OR ANY OTHER
      ENTITY FOR ANY SPECIAL,  CONSEQUENTIAL,  INCIDENTAL,  OR INDIRECT DAMAGES,
      HOWEVER CAUSED, ON ANY THEORY OF LIABILITY, AND REGARDLESS OF WHETHER SUCH
      PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. THIS LIMITATION
      SHALL  APPLY  NOTWITHSTANDING  ANY  FAILURE  OF  ESSENTIAL  PURPOSE OF ANY
      LIMITED REMEDY.

      7.2   Monetary Limitation.

      As a material  condition of Vistar  entering into this  Agreement,  and in
      regard to any causes of action arising out of or related to this Agreement
      including, but not limited to, claims of negligence, breach of contract or
      breach of warranty or  otherwise,  or any other claim whether in contract,
      tort or any other legal  theory,  CMDC agrees that the liability of Vistar
      shall in no event exceed the total amount  already paid by CMDC to Vistar,
      including all Royalties, under this Agreement.

8.    INTELLECTUAL PROPERTY RIGHTS AND CONFIDENTIALITY

      8.1   Intellectual Property Rights.

          (i)  CMDC acknowledges that VISTAR owns:

               a.   Background Technology,  and the Intellectual Property Rights
                    therein;
               b.   the  MST  Technology  including,   without  limitation,  all
                    hardware and software designs and implementations associated
                    with the MST Technology and the Intellectual Property Rights
                    therein; and
               c.   other  Vistar   Confidential   Information   including   all
                    Intellectual Property Rights therein.

          (ii) VISTAR acknowledges that CMDC owns:

               a.   the   Intellectual   Property  Rights  to  those  additional
                    components of the MST which are not MST Technology or Vistar
                    Background Technology as defined in this Agreement; and

               b.   other  CMDC  Confidential   Information   including  without
                    limitation  to  the   Specifications  and  all  Intellectual
                    Property Rights therein.


                                      10





      8.2   Use of Marks.

      All documents (in whatever form,  including machine readable or electronic
      form) and other product materials owned by a Party must contain all proper
      Marks,  legends,  copyright  notices and patent  markings  reflecting  the
      Intellectual   Property  Rights  of  that  Party  in  such  documents  and
      materials.  This License  Agreement gives neither Party any proprietary or
      other rights whatsoever in the other Party's Marks.

      8.3   Confidentiality.

            Each Party agrees:

          (i)  to observe  confidentiality  with  respect  to the other  Party's
               Confidential Information;

          (ii) not to disclose,  or permit any third party or entity  access to,
               the  Confidential  Information (or any portion  thereof)  without
               prior written permission of the Disclosing Party; and

          (iii)to ensure that any  employees,  or any  authorized  third parties
               who receive access to the Confidential  Information,  are advised
               of the  confidential  and  proprietary  nature  thereof  and  are
               prohibited  from  copying,  utilizing or otherwise  revealing the
               Confidential Information; and

          (iv) without limiting the foregoing,  each Party agrees to employ with
               regard  to  the  Confidential   Information  procedures  no  less
               restrictive than the procedures used by such Party to protect its
               own similar  confidential and proprietary  information,  but at a
               minimum commercially reasonable procedures.

      8.4   Breach and Survival.

      It is expressly agreed and understood by the Parties that a breach of this
      Section 8 shall be deemed a Material Breach of this Agreement which breach
      will give rise to  injuries  that are not fully  compensable  by  damages.
      Accordingly,  the  Party  not in  breach  shall be  entitled  to apply for
      equitable  relief.   This  Section  8  shall  survive  the  expiration  or
      termination of the Agreement in any manner whatsoever.




                                      11





9.    INTELLECTUAL PROPERTY RIGHTS INDEMNITY

      9.1   Defense by CMDC.

            Except as provided in Subsection  9.2 below,  CMDC shall defend,  at
            its own expense,  any action  brought  against  Vistar to the extent
            that such  action is based  upon an IP Claim  that the use of MST by
            CMDC,  its  permitted   licenses   and/or   assigns   infringes  any
            Intellectual Property rights of a third party.

      9.2   Defense by Vistar.

          (i)  Vistar shall defend,  at its expense,  any action brought against
               CMDC to the  extent  that it is based on a claim  that the use of
               the MST Technology developed by Vistar infringes any Intellectual
               Property Right of any third party ("IP Claim" or "IP  Claimant").
               CMDC agrees to notify Vistar promptly in writing of any IP Claim,
               to permit  Vistar to defend,  compromise  or settle such IP Claim
               and to provide  reasonably  available  information and assistance
               regarding such IP Claim;  provided that if Vistar fails to retain
               defense  counsel  for any such  claim,  CMDC may  retain  its own
               defense counsel and defend against such IP Claim.
          (ii) Should  the MST  Technology  in the  opinion  of  Vistar's  Legal
               Counsel,  be likely to become the subject of an IP Claim,  Vistar
               shall either:

               a.   Procure for CMDC, at no cost to CMDC,  the right for CMDC to
                    continue  exercising  the  rights  granted  under  the  CMDC
                    License;
               b.   Replace or modify the MST  Technology  at no cost to CMDC to
                    make the MST  Technology  non-infringing,  provided that the
                    replacement    or   modified   MST    Technology    provides
                    substantially similar functionality and performance; or
               c.   If  neither  a. or b.  is  technically  feasible,  terminate
                    CMDC's then existing  rights under this Agreement and refund
                    of all  amounts  already  paid to Vistar by CMDC  under this
                    Agreement, including all Royalties.

     9.3  Limitation.  Vistar  shall have no  liability  for any IP Claim to the
          extent  that it is based  upon the  operation  or use of CMDC or third
          party  designs,  applications,  products or  materials  not  supplied,
          specified or approved by Vistar in writing and such IP Claim would not
          have occurred but for the use of such  unapproved  CMDC or third party
          designs, applications, products or materials, even if the operation or
          use of such designs, applications,  products or materials is permitted
          by the terms of CMDC's License.

                                      12





     9.4  Notification of Unauthorized Use. Each Party shall promptly notify the
          other in writing upon its discovery of any allegedly  unauthorized use
          or infringement of the MST Technology or the Confidential Information.
          In the event  that an  action  is  brought  regarding  such  allegedly
          unauthorized  use or  infringement,  the Parties shall  co-operate and
          provide full  information  and  assistance to each other in connection
          with any such action or proceeding.

10.   REPRESENTATIONS, WARRANTIES

      10.1  General Representations and Warranties.

            Each Party represents and warrants to the other Party that:

          (i)  it is  authorized  to enter into this  License  Agreement  and to
               perform its obligations hereunder;
          (ii) except as otherwise set forth in this License Agreement,  it will
               not impair or encumber,  in any manner, the Intellectual Property
               Rights or other ownership rights of the other Party;
          (iii)the execution of this  Agreement  does not violate any applicable
               law, statute or breach any agreement or covenant to which it is a
               party or is bound; and
          (iv) the  performance  of  its  rights  and  obligations   under  this
               Agreement  will not infringe up on any third  party's  trademark,
               copyright, patent or trade secret.

      10.2  Vistar Warranties:

          (i)  Vistar   represents   and  warrants   that  the  MST   Technology
               Deliverables provided by Vistar under this Agreement are designed
               to be used prior,  to, during and after  Calendar year 2000 A.D.,
               and that the said MST  Technology  will operate  during each such
               time period  without  error  relating to date data,  specifically
               including  any error  relating  to, or the  product of, date data
               which represents or references  different  centuries or more than
               one century.
          (ii) The MST Technology shall substantially conform to and achieve the
               functionality stated in the Specifications.

      10.3  No Other Representations, Warranties or Guarantees.

      EXCEPT  FOR  THE  EXPRESS  WARRANTIES  STATED  HEREIN,  NEITHER  PARTY  IS
      PROVIDING TO THE OTHER PARTY ANY OTHER EXPRESS OR IMPLIED WARRANTIES UNDER
      THIS AGREEMENT,  INCLUDING,  WITHOUT LIMITATION, ANY IMPLIED WARRANTIES OF
      MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

                                      13





11.   TERMINATION

      11.1  Early Termination.

          (i)  Either Party.  This License  Agreement shall  terminate,  without
               notice,

               a.   upon  the   institution   by  either  Party  of  insolvency,
                    receivership or bankruptcy proceedings,
               b.   upon the  institution  against  either Party of  insolvency,
                    receivership or bankruptcy proceedings,  if such proceedings
                    are not  dismissed  within  ninety  (90) days of the Party's
                    receipt of notice of such proceedings against it;
               c.   upon either  Party's making an assignment for the benefit of
                    creditors of all or part of its assets, or
               d.   upon either Party's dissolution or ceasing to do business or
                    upon  a  decision  by  the  Shareholders   and/or  Board  of
                    Directors of either Party to cease to do business.
          (ii) Upon the  occurrence of any of the events set forth in Subsection
               11.1 (i),  the Party  making the  filing,  assignment,  receiving
               notice  thereof,  or dissolving  or ceasing to do business  shall
               immediately inform the other Party in writing of such event.
          (iii)Upon the  occurrence of any of the events in Subsection  11.1(i),
               in the event that  Vistar is the party with  respect to which the
               event occurred, CMDC shall be entitled to exercise the rights set
               out in Section 12.

      11.2  Termination for Material Breach.

            Except in the case of a Material  Breach of Sections 8, in the event
            of a Material Breach of any provision of this License Agreement, the
            non-breaching  Party may terminate this License  Agreement by giving
            thirty  (30)  days  prior  written  notice to the  breaching  Party;
            provided,  however,  that this License Agreement shall not terminate
            if the breaching  Party has cured the breach prior to the expiration
            of such thirty  (30) day period,  or if subject to the terms of this
            Agreement  any Dispute  regarding  such breach has been  referred to
            Arbitration in accordance  with the provisions of Section 13. In the
            event of a  Material  Breach  of  Sections  8, if the  breach is not
            capable  of  being  cured  to  the  reasonable  satisfaction  of the
            non-breaching Party, the Party not in default may elect to terminate
            this License  Agreement  upon ten (10)  business  days prior written
            notice to the Party in default. In such circumstances, the Agreement
            shall  terminate  at the  conclusion  of this notice  period  unless
            otherwise mutually agreed upon by the Parties.

                                      14





      11.3  Effects of Termination.

            In addition to pursuing the remedies available under the law, in the
            event of the termination of this Agreement by CMDC,

            Vistar may revoke  CMDC's  License  upon five days  written  advance
            notice. Upon receipt of such notice CMDC shall:

            (i)   immediately  cease all  development  and marketing of MSTs and
                  all use of Vistar Confidential Information,  Marks, equipment,
                  materials and documentation; and
            (ii)  Pay all amounts owing to Vistar including all amounts owing as
                  a result of Section 4 and Subsections 3.3 and 15.19.

12.   SOURCE CODE

Vistar shall  deliver  into escrow the VSLP source code for the Viterbi  decoder
and frequency estimator modules.  The Parties hereby agree that the escrow agent
shall be legal counsel for Vistar, more particularly:

                        Nelligan Power
                        Law Offices
                        66 Slater Street, 19th Floor
                        Ottawa, Ontario
                        K1P 5H1

                        Attention: Stephanie M. Traynor

Upon the  occurrence  of an event set out in Subsection  11.1(i),  provided only
that  Vistar is the party with  respect to which the event  occurred,  the above
described  source code shall be  released to CMDC and Vistar  shall be deemed to
have  granted CMDC a license to such source code on the same terms as set out in
Subsection 3.2.



                                      15





13.   ARBITRATION AND DISPUTE RESOLUTION

      13.1  Disputes.

      In the event of any Dispute, each Party shall provide the other Party with
      written notice setting forth the outstanding  issues and positions of such
      Party   regarding   such  Dispute.   It  shall  be  the   obligation   and
      responsibility  of each  Party  to use his or her  best  efforts,  in good
      faith,  to resolve any such  Dispute,  in  co-operation  with  appropriate
      representatives of both Parties, as soon as reasonably possible.

      13.2  Arbitration.

      If the Parties are unable to resolve a Dispute  within thirty (30) days of
      their initial  discussions  concerning  such Dispute,  except for Disputes
      arising under Section 8, any such Dispute shall be settled by  arbitration
      in accordance with the Ontario Arbitration Act. The Parties shall mutually
      select a single  arbitrator.  If the  Parties  are  unable to agree on the
      selection  of an  arbitrator  within  thirty (30) days of  starting  their
      selection process,  then the number of arbitrators shall be three (3), and
      each Party  shall  select one  arbitrator  and the two  arbitrators  shall
      mutually  select and agree upon the third  arbitrator.  The Parties  shall
      provide the arbitrators and any expert  witnesses with all information and
      resources they may require to make their  decision.  Any failure of either
      Party to comply  with such  request of the  arbitrators  shall be deemed a
      Material Breach of this License Agreement.  An arbitration  decision shall
      be  binding.  The  prevailing  Party may enter such  decision in any court
      having competent  jurisdiction and failure to comply with such arbitration
      decision shall result in a Material Breach by the non-complying Party. The
      arbitration  proceeding  shall be  conducted  in the  English  language in
      Ottawa,  Ontario,  unless the  Parties  agree in  writing  to conduct  the
      arbitration  in  another  location.  Failure  of  either  Party to  attend
      arbitration shall result in a Material Breach by the absent Party.

14.   CECOM OBLIGATIONS

Vistar  acknowledges  and agrees to be bound by the flowdown  clauses imposed by
CECOM set forth in  Schedule E attached  hereto and  incorporated  by  reference
herein.  For the purpose of this  Schedule,  Vistar is deemed to be the "Seller"
and CMDC is deemed to be the "Buyer"  therein.  As an  exception  to  Subsection
15.2,  Vistar  acknowledges  and agrees that the rights of the Government of the
United  States as reflected in Schedule E shall be governed by the U.S.  Federal
Laws and to the extent  that  State law may  apply,  by the laws of the State of
Maryland.  Vistar's  obligations  with  respect to  Schedule  E shall  terminate
concurrent with the termination of CMDC's obligations thereunder.

                                      16





15.   GENERAL PROVISIONS

      15.1  Independent Contractors.

            The  relationship  of Vistar and CMDC  established  by this  License
            Agreement is that of independent contractors,  and nothing contained
            in this License Agreement 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 Party for any purpose whatsoever.

      15.2  Governing law.

      This License  Agreement  shall be governed by and construed under the laws
      of the  Province of Ontario and the laws of Canada,  without  reference to
      conflicts of law principles thereof.

      15.3  Notices.

      All  formal  notices  hereunder  shall be in  writing  and shall be deemed
      effective upon receipt when delivered by hand, overnight delivery courier,
      by facsimile  transmission  (provided  such notice is also given in any of
      the other  manners  set forth  herein)  or when  mailed by  registered  or
      certified mail (return receipt requested), postage prepaid, to the Parties
      at the  addresses  listed  below (or at such other  address for a Party as
      shall be specified by like notice).

            If to Vistar:

                  Vistar Telecommunications, Inc.
                        Suite 1410, 427 Laurier Avenue West
                        Ottawa, Ontario K1G 3J4
                        Attention: Vice President, Technology and Programs

            If to CMDC:

                  Comtech Mobile Datacom Corp.
                  19540 Amaranch Drive
                  P.O. Box 2126
                  Germantown, MD  20875-2126
                  Attention:  Joel Alper, President



                                      17





      15.4  Assignability and Binding Effect.

      CMDC may not assign this License  Agreement to any third party without the
      prior written  consent of Vistar,  which consent shall not be unreasonably
      withheld.

      15.5  Inurement.

      Subject  to the terms  and  conditions  of this  License  Agreement,  this
      License  Agreement  shall be binding  upon and inure to the benefit of the
      Parties hereto and their permitted successors and assigns.

      15.6  Amounts in U.S. Currency.

      Except as  otherwise  specified  in this  License  Agreement,  all amounts
      payable  under this  Agreement or the Schedules are in the currency of the
      United States.

      15.7   Pre-Printed Terms Void.

      The  pre-printed  terms  on any  order,  acknowledgment,  packing  slip or
      similar  document  provided by one Party to the other in  connection  with
      this License Agreement shall be of no force or effect.

      15.8  Notice of Actions.

      Each  Party  agrees  to  notify  the  other  Party  immediately  upon  the
      commencement  of or threat of  commencement  of any claim,  suit or action
      brought or that may be brought against either Party,  where the outcome of
      such claim,  suit or action may affect the rights or obligations of either
      Party under this License Agreement.

      15.9  Headings.

      The headings  contained in this License  Agreement are for  convenience of
      reference  only and shall not  control the  interpretation  of any term or
      condition contained herein.

      15.10 Severability.

      If any  provision  of  this  License  Agreement  is  invalid,  illegal  or
      unenforceable in any jurisdiction,  such provision shall be deemed amended
      to conform to applicable laws so as to be valid and enforceable, or, if it
      cannot be so amended  without  materially  altering  the  intention of the
      Parties  hereto,  it shall be stricken,  and the remainder of this License
      Agreement shall remain in full force and effect.

                                      18





      15.11 Cumulation of Remedies.

      Except as  otherwise  expressly  stated  in this  License  Agreement,  all
      remedies  available to either  Party for breach of this License  Agreement
      are  cumulative  and may be exercised  concurrently  or separately and the
      exercise of any one remedy  shall not be deemed an election of such remedy
      to the exclusion of other remedies.

      15.12 Equitable Relief.

      The Parties agree that certain breaches of this Agreement may give rise to
      injuries that are not fully compensable by damages. Therefore, the Parties
      acknowledge and agree that in addition to any other remedies  available at
      law, and  notwithstanding the provisions of Section 12.2, a Party shall be
      entitled to apply to a court of competent jurisdiction and seek injunctive
      or  other  equitable  relief,  including,  without  limitation,   specific
      performance,  from the other Party to enjoin any breach by the other Party
      of the provisions of this Agreement.

      15.13 Interest.

      Any amount that is not paid when due will bear  interest  until fully paid
      at the rate of the  lesser of (i) one  percent  and one half  (1.5%),  per
      month compounded monthly, or (ii) the highest rate permitted by applicable
      law.  Vistar shall also be entitled to recover its costs and expenses,  if
      any, incurred in collecting such amount.  Vistar's entitlement to interest
      shall in no way effect CMDC's  obligations  to make payments in accordance
      with Section 4 of this Agreement, and Vistar's acceptance of such interest
      shall not be deemed to be waiver of any of CMDC's  obligations  respecting
      payments.

      15.14 Waiver.

      No term or provision  hereof shall be deemed waived and no breach  excused
      unless such waiver or consent  shall be in writing and signed by the Party
      claimed to have waived or  consented,  and such written  waiver shall only
      serve to waive or  excuse,  as the case may be, the  particular  breach to
      which it applies and no other.

      15.15 Force Majeure.

      Each Party shall be excused from performance  under this License Agreement
      and shall  have no  liability  to the other  Party for any period if it is
      prevented  from  performing  any of its  obligations  (other than  payment
      obligations)  in whole or in part,  as a result of delays caused by an act
      of God, war, civil disturbance,  company or industry-wide labour disputes,
      or other cause  beyond its  reasonable  control  and such  non-performance
      shall not be a default under,  or grounds for  termination of this License
      Agreement.  However,  if a Force Majeure event continues for more than one
      hundred and eighty  (180) days,  then the Party whose  performance  is not
      affected  by the Force  Majeure  shall  have the right to  terminate  this
      License Agreement.

                                      19





      15.16 Schedules.

      Schedules A, B, C, D and E of this License  Agreement form part of and are
      incorporated  into this License  Agreement as fully and  effectively as if
      they  were  set  forth  in this  License  Agreement.  In the  event of any
      conflict or inconsistency between the provisions of this License Agreement
      and one or more of the Schedules,  the conflict or inconsistency  shall be
      resolved in favour of the License Agreement.

      15.17 Acknowledgment.

      Each Party acknowledges that it has read this License Agreement, including
      the  Schedules  attached  hereto and forming part  hereof,  and each Party
      understands and agrees to be bound by its terms and conditions.

      15.18 Changes to this License Agreement.

      No changes to any  provision  of this  License  Agreement,  including  the
      Schedules hereto,  shall be effective unless reduced to writing and signed
      by the Parties hereto.

      15.19 Expenses.

      Travel and living expenses incurred by Vistar shall be invoiced to CMDC at
      cost  with  associated  receipts.  Travel  and  living  expenses  must  be
      authorized in advance by CMDC.

      15.20 Operating Systems.

      To  the  extent  permitted  by  law  or  Vistar's   existing   contractual
      obligations,  Vistar  agrees to make  available  to CMDC the  Precise  MQX
      Operating System license  associated with the CMDC terminal for a price of
      $XX.

      15.21 Survival.

      Except as otherwise provided in this License Agreement,  the provisions of
      Sections 4, 5, 7, 8, 9, 10 and 15 with the exception of Subsections 15.15,
      15.17,  15.18,  15.19, 15.20 and Subsections 3.1, 3.3 and 13.2, as well as
      the guarantees and/or indemnifications in Subsections 3.2(iii) and 3.2(iv)
      shall survive the termination or rescission of this License  Agreement for
      any reason.  Nothing in this License Agreement shall be construed so as to
      extend or override a  statutory  limitation  on the time within  which any
      action or actions based on this License Agreement may be brought.

                                      20





      15.22 Publicity.

      Any press  release or other  publication  by either  Party  regarding  the
      existence  or terms of this  License  Agreement  must be  approved by both
      Parties prior to its publication.

      15.23 Entire Agreement.

      This License Agreement, together with Schedules A, B, C, D and E set forth
      and  constitutes  the entire  agreement  by and between  the Parties  with
      respect to the  development and licensing of MST Technology and supersedes
      any and all prior agreements,  understandings and representations  made by
      the Parties  concerning the subject matter of this Agreement.  For greater
      certainty it is expressly  acknowledged  and agreed that  co-incident with
      the execution of this  agreement the MOA and  amendments  thereto shall be
      terminated and each Party releases the other of all obligations under that
      agreement.



                                      21




      WHEREOF,  Vistar and CMDC have caused this  License  Agreement  to be duly
executed by their  respective  authorized  representatives  as of the  Effective
Date.

Vistar Telecommunications, Inc. (Vistar)        Comtech Mobile Datacom Corp.
(CMDC)

By:                                             By:




            /s/                                       /s/
Name: Dr. Michael Zuliani                       Name: Joel Alper

Title:President and Chief Executive Officer     Title: President

Date: August 31, 1999                            Date:  August 9, 1999



                                      22