<PAGE>
                                                                   EXHIBIT 10.13

                                                   [HUGHES NETWORK SYSTEMS LOGO]

           8050025



                              TERMS AND CONDITIONS

                                       FOR

                                    38GHZ ODU

                                     BETWEEN

                             HUGHES NETWORK SYSTEMS
                    A HUGHES ELECTRONICS CORPORATION COMPANY
                             11717 EXPLORATION LANE
                           GERMANTOWN, MARYLAND 20876

                                      AND

                               ENDGATE CORPORATION
                                 321 SOQUEL WAY
                           SUNNYVALE, CALIFORNIA 94086

                              DATE: MARCH 13, 1998

                           CONTRACT NO.: JBG-020798-1









[*] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.


<PAGE>



                        NOTICE OF PROPRIETARY INFORMATION

All information contained in or disclosed by this document is confidential and
proprietary to Hughes Network Systems, Inc. By accepting this material the
recipient agrees that this material and the information contained therein will
be held in confidence and will not be reproduced, disclosed, or used in whole or
in part except for purposes of this document.



                                       ii
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                                                           Subcontract Agreement
                                                                8050025 (12/93P)

                              TERMS AND CONDITIONS

     THIS CONTRACT dated the March 13, 1998, made between Hughes Network
Systems, a Hughes Electronics Corporation company, having its principal place of
business at 11717 Exploration Lane, Germantown, Maryland 20876 (hereinafter
called "HNS"), and Endgate Corporation having its principal place of business
at 321 Soquel Way, Sunnyvale, CA 94086 (hereinafter called the "Contractor" or
"Endgate").

                                   WITNESSETH:

     WHEREAS HNS desires to buy and Contractor desires to sell Equipment and
Services as hereinafter specified and the Parties desire to define the terms and
conditions under which such Equipment and Services will be furnished.

     NOW THEREFORE, the Parties hereto, in consideration of the mutual covenants
herein expressed, agree with each other as follows:

ARTICLE   SCOPE OF WORK

     Contractor shall provide the necessary personnel, material, services,
equipment and facilities to perform the Work specified in the Statement of Work
(Exhibit A) entitled "Statement of Work For Manufacture Of A 38-GHZ Radio
Integrated Outdoor Unit For Subscriber And Hub Stations" Revision 6 and dated
March 18, 1998, and the specification 1024668 at it's then current revision and
1025231 at it's then current revision which are attached hereto and made a part
of this Contract.

ARTICLE   STRATEGIC RELATIONSHIP

     The Parties agree that they are hereby entering into a strategic
relationship in which Contractor shall supply millimeter wave equipment to HNS
in accordance with this Contract. Contractor agrees to give the highest priority
commitment for the life of this relationship for the following elements:

     1.   Factory capacity to ensure timely delivery of Work ordered by HNS,
     2.   Design services and product changes to permit this Work to retain its
          technical leadership and competitive position in the market and to
          permiffadapt its use at other frequency bands as indicated in the SOW.

     Contractor hereby grants to HNS market exclusivity for the
Point-To-Multipoint market for a [*] after completion of Acceptance of the Work
or any changes, enhancements, or derivatives before offering to sell such Work
or modified Work to others. Exclusivity will terminate if HNS fails to order [*]
of the forecasted quantity for a period of [*]. The first year Production
forecast for this Contract is [*]. HNS agrees to provide the Contractor with a
first opportunity to bid on requirements for new Point to Multipoint assemblies
at frequencies of 18 GHz and above.


[*] CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTIONS.


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                                                           Subcontract Agreement
                                                                8050025 (12/93P)

ARTICLE    PRICE AND PAYMENT

     A.   For the full, satisfactory, and timely performance of all the
          requirements of this Contract, Contractor shall be entitled to payment
          by HNS of the amount indicated in Purchase Order P241537 and
          subsequent associated purchase orders, in accordance with this Article
          and paragraph C of the Article entitled PRODUCTION PHASE AND PURCHASE
          ORDERS. In any event the total amount associated with the Development
          Phase shall not [*] and shall be paid based on the successful
          conclusion of the Development milestones as shown in paragraph C of
          this Article. This amount, which shall be paid to Contractor in
          accordance with this Article, includes all taxes, duties and similar
          liabilities whatsoever and all charges for packaging and crating
          deliverable items to destination(s) in the United States designated by
          HNS, except as stated in Paragraph B below.

     B.   Except with respect to any State or local sale, or use taxes on the
          sale to HNS or use by HNS of the items delivered under this Contract,
          Contractor shall assume responsibility for and shall save HNS harmless
          from all taxes, duties, and similar liabilities which may be required
          under any applicable Federal, State, or local law or laws and which
          become due by reason of the performance of Work under this Contract,
          and shall comply with all requirements of said laws, including any
          interest payment or penalties related to or arising from such taxes,
          duties and similar liabilities

     C.   Without limiting the obligations of Contractor to comply with all the
          requirements of this Contract, FINS agrees to make payments to
          Contractor in accordance with the following schedule:

                              DEVELOPMENT PHASE

          MILESTONE                                PAYMENT
          ---------                                --------
          [*]                                      [*]

          where Acceptance is defined by Chapter 5 of the SOW, but excludes
          "Production Testing".

     D.   Pursuant to this Article, the applicable amounts due Contractor shall
          be paid within thirty (30) days net after receipt of an invoice for
          the Development Phase and sixty (60) days net after receipt of an
          invoice for the Production Phase in which Contractor warrants that the
          Work that is the subject of the invoice has been completed in
          accordance with the requirements of this Contract, and that all
          conditions established by this Contract as prerequisite to payment of
          the

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


                                       2
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                                                           Subcontract Agreement
                                                                8050025 (12/93P)

          invoice have been fulfilled. All invoices submitted by Contractor
          shall refer to purchase order P241537, and subsequent purchase orders,
          if any, and shall be sent in triplicate to:

          Hughes Network Systems, Inc.
          11717 Exploration Lane
          Germantown, Maryland 20876
          Attn: Accounts Payable

     E.   By mutual agreement between HNS and Contractor, HNS may make
          payments other than as specified above for units of Work completed,
          but such payments shall not be deemed as evidence that the Work for
          which payments are made has been performed satisfactorily and shall
          not relieve Contractor from responsibility for full and satisfactory
          completion of all the Work required.

     F.   In consideration of the Strategic Relationship and Development Phase
          payments set forth above, Contractor represents and warrants that the
          price charged for the Work covered by this Contract shall include a
          [*] over all other customers of Contractor for similar Work in similar
          quantities. This discount shall be in effect only for a four year
          period starting after the Development Phase.

ARTICLE    PRODUCTION PHASE AND PURCHASE ORDERS

     A.   Upon commencement of the Production Phase, if any, orders for Products
          would be made by the issuance of Purchase Orders to Contractor.
          Contractor will deliver Product ordered under valid Purchase Order(s)
          issued by HNS within a maximum of ninety (90) days from the date of
          order, or such longer period of time as HNS may desire. Purchase
          Orders will include the following (at a minimum):

               1. HNS part number of Product being ordered;
               2. Quantity ordered;
               3. Unit price Product(s);
               4. Shipping instructions;
               5. Delivery schedule.

     B.   Production Purchase Order delivery dates are subject to the following
          terms for rescheduling:

               1.   Within 30 days of scheduled delivery Work Product may not be
                    canceled or rescheduled;

               2.   Within 31 to 90 days of scheduled delivery Work Product may
                    be rescheduled out a maximum of ninety (90) days from the
                    original scheduled due date;

               3.   Quantities of Work on order with scheduled delivery more
                    than 90 days from reschedule notice may be canceled or
                    rescheduled without liability.

     C.   The initial prices for the [*]. The table below represents the initial
          not to exceed, volume based, pricing

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


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                                                           Subcontract Agreement
                                                                8050025 (12/93P)

          prior to the completion of the design and experiencing the actual
          manufacturing costs and O/H. After commencement of the Production
          Phase, if any, and prior to shipment of the [*], HNS and Contractor
          will negotiate the pricing for the subsequent Subscriber and the HUB
          units. The subscriber pricing will [*]. The HUB pricing will follow
          similar guidelines and [*].

                SUBSCRIBER UNITS                         HUB UNITS

           QUANTITY            UNIT PRICE      QUANTITY             UNIT PRICE
           [*]                 [*]             [*]                  [*]

     D.   It is understood, by both Parties that the target pricing of the
          Subscriber units beyond the [*] will require an end cost to HNS of
          [*]. To achieve this target price, after commencement of the
          Production Phase, if any, and prior to shipment of the [*], HNS and
          Contractor agree to negotiate a cost reduction plan in which both
          Parties will work together to achieve cost reductions for the
          Products. Such plan will include details of the process both Parties
          will follow to identify potential cost reductions and how any cost
          reductions achieved will be shared by both Parties subject to
          achieving the target price. It is understood that there will be a high
          level of commonality in design, materials, and manufacturing processes
          between the Subscriber unit and Hub unit. Therefore, any identified
          price reductions for the Subscriber unit will be incorporated in the
          Hub unit price.

     E.   At HNS sole option the quantities on order may be increased
          according to the following schedule:

              Days Prior To Scheduled Delivery        Allowable Increase Percent

              [*]                                     [*]

     F.   HNS non-binding production forecast, which is not to be interpreted as
          a commitment, is for [*] to be delivered over a four year period
          starting after the Development Phase.

ARTICLE    DELIVERY

     The Work required to be delivered to HNS by Contractor under this
Contract shall be in accordance with Attachment A, Statement Of Work.

[*] CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE    ACCESS TO WORK IN PROGRESS AND DATA

     All Work in progress under this Contract and data and documentation related
to this Contract are subject to continuous examination, evaluation and
inspection by HNS at any reasonable time during the period of this Contract on a
non-interfering basis in conformity with Contractors physical security program.
Thereafter, to the extent that such data and documentation is of a type normally
retained by Contractor, it shall continue to be available for such purposes.

ARTICLE    INSPECTION AND TESTS

     A.   Inspections may be made at all reasonable times on a non-interfering
          basis in conformity with Contractors physical security program by
          HNS or its designated representative(s) at Contractor's site(s).
          Contractor agrees to use best efforts to gain access for HNS to its
          Subcontractors site(s) for inspections if requested by HNS.

     B.   Contractor shall give HNS adequate notice of all testing in
          accordance with the Statement Of Work to be conducted under this
          Contract and shall permit HNS to have its representative(s) witness
          such tests.

     C.   When Contractor notifies HNS that the Work fully conforms with the
          requirements of this Contract, in accordance with the Statement Of
          Work, and is ready for inspection and test at Contractor's and/or its
          Subcontractor's site(s), HNS may conduct an inspection and shall
          authorize the conduct of such test(s) in accordance with Exhibit A.
          After completion of the test(s), HNS shall notify Contractor either
          that the Work is satisfactory for production and/or shipment to the
          destination specified by HNS, or of those particulars in which the
          Work does not conform with the requirements of this Contract. Where
          any Work does not conform with the requirements of this Contract, then
          upon remedy of such nonconforming items to meet the requirements of
          this Contract, Contractor shall notify HNS that the Work is ready for
          reinspection and/or retest at Contractor's and/or its Subcontractor's
          site(s). HNS may conduct such reinspection and/or authorize the
          conduct of such retest in accordance with the requirements of
          Exhibit A. Upon successful completion of such inspection and test,
          HNS'S shall notify Contractor that the Work is satisfactory for
          production and/or shipment to the destination specified by HNS.

     D.   Remedy of the nonconforming items referred to in this Article shall be
          promptly made by Contractor, at its expense, upon receipt of notice
          thereof from HNS. If Contractor fails to remedy any such nonconforming
          items(s), HNS may elect either (1) to have any or all such
          nonconforming item(s) remedied through other means, in which event
          Contractor shall pay the costs of so remedying such nonconforming
          item(s) [*] of such nonconforming items, or (2)accept the Work and
          reduce this Contract price by an equitable amount.

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE    ACCEPTANCE

     A.   AFTER receipt at destination, HNS shall promptly inspect the Work
          received. Within a reasonable time after such inspection, HNS shall
          either accept the Work or reject the Work, and notify Contractor in
          writing of those rejected items, specifying reason(s) for rejection.
          Rejected items shall be promptly corrected by Contractor at its
          expense, which shall include all related costs for repair or
          replacement of the rejected item(s) and all applicable shipping
          charges. Upon correction of such rejected item(s), the Work shall be
          accepted by HNS.

     B.   If Contractor fails to correct any such rejected item(s), HNS may
          elect either (1) to have any or all such rejected item(s) remedied
          through other means, in which event Contractor shall pay the costs of
          so remedying such rejected item(s) [*] of such rejected items; or (2)
          accept the Work and reduce this Contract price by an equitable amount.

ARTICLE    TITLE AND ASSUMPTION OF RISK

     Contractor shall convey good title, free from any claim or encumbrance, to
HNS for all items either delivered under this Contract or that become the
property of HNS pursuant to this Contract FOB Sunnyvale, California. Any loss
or damage to such items prior to passing of title shall be at Contractor's risk.

ARTICLE    WARRANTIES

     A.   Contractor represents that it is a regular dealer in, or manufacturer
          of, the Work and warrants that all Work furnished under this Contract
          is free from defects in materials, design and workmanship, and is in
          conformity with all requirements of this Contract.

     B.   Notice of any defect or nonconformity under this Contract shall be
          given to Contractor within twenty four (24) months from the date of
          acceptance by HNS, PROVIDED, HOWEVER, that notice of a defect that is
          latent or was caused or concealed by fraud or such gross mistakes as
          amount to fraud may be given at any time.

     C.   HNS shall have the right at any time during the period of this
          warranty, and irrespective of prior inspections or acceptances, to
          reject Work not conforming to the above warranty and require that
          Contractor, at its expense, correct or replace such Work within ten
          (10) business days with conforming Work. If Contractor fails to
          correct or replace such nonconforming Work promptly after
          notification, HNS may, by contract or otherwise, correct or replace
          such nonconforming Work and Contractor shall be liable for and shall
          pay to HNS the cost of such correction or replacement [*] of the
          non-conforming Work.

     D.   In addition to the foregoing, Contractor agrees to assign, and hereby
          does assign, to HNS any other warranties as Contractor or its
          Subcontractor(s) customarily offer in connection with the sale of
          similar items, including sales to Contractor's or the pertinent
          Subcontractor's most favored purchaser. Any such assignment shall not
          relieve Contractor of any of its responsibilities under this Contract.
          Contractor shall notify HNS of each warranty and, upon

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

          receipt of such warranty, shall deliver to HNS any documents issued by
          the warrantor evidenoing such warranty.

     E.   In addition to correction of any defects in accordance with the
          warranty provisions of this Agreement, the following provisions shall
          apply with respect to multiple failures of the work resulting from the
          same defect in design, materials or manufacturing process ("Pattern
          Defects"): A Pattern Defect shall be established when HNS, in
          cooperation with Contractor, shall reasonably demonstrate that [*] of
          the Product delivered is failing from the same defect in design,
          material or manufacturing process. In the event that a Pattern Defect
          is demonstrated in any lot Contractor will promptly (a) modify the
          work design, materials and/or manufacturing process so that the
          Pattern Defect will no longer occur, (b) upgrade all work returned by
          HNS to Contractor for any other reason and which are covered by the
          provisions of this Article such that the Pattern Defect with respect
          to such work shall be corrected. Further, in the event a Pattern
          Defect is established as set forth above, Contractor will provide the
          serial number of the work in the affected lot, and HNS may recall all
          work of such lot(s) covered by the provisions of this Article, and
          Contractor shall modify all such recalled work at its expense
          including two way shipping costs such that the Pattern Defect with
          respect to such work is corrected.

     F.   Contractor agrees to offer an extended warranty for Products in
          service where the standard 24 month warranty described above has
          expired. The extended warranty must be backwards compatible, i.e.,
          Contractor will repair returned models that are of earlier vintage
          than the then current production model to their original vintage, and
          offer provisions equal to or better than those provided in the
          standard 24 month warranty described in the preceding paragraphs. The
          extended warranty shall be offered with an option to purchase on an
          annual basis(includes all units returned during that extended warranty
          period) or per unit basis. The cost for any extended warranty shall be
          in accordance with the following schedule:

            WARRANTY PERIOD             PRICE
            ---------------             -----

            [*]                         [*]

            Per Unit                    TBD

     G.   Contractor agrees to maintain a stock of Field Replaceable Units (FRU
          Stock), which consists of system components, and parts and to provide
          ability to ship said FRU to HNS or it's customer within 24 hours of
          notice of a failure of Contractors Product. Quantity of FRU stock to
          be mutually agreed upon by HNS and Contractor.

     H.   In accordance with Exhibit A, Statement Of Work Section 2.6.6, Out of
          Box Failure Rate(OBFR) shall not exceed, [*]. Beginning with the [*]
          the OBFR shall not exceed [*]. In the event that the cumulative OBFR
          exceeds [*] HNS will notify Contractor in writing. Contractor agrees
          to take steps to solve the problems causing such failures and shall
          within 10

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

          working days analyze the problem(s), prepare and submit an action plan
          indicating what steps Contractor will take to remedy the problem, and
          promptly initiate corrective action on delivered and future production
          units. Furthermore, Contractor agrees to use it's best efforts to
          achieve an overall goal of [*] OBFR as soon as possible.

     I.   Contractor warrants that there is nodate specific software contained
          in the Product(s) delivered under this Contract and that the
          Product(s) will not be adversely affected by the year 2000 date.

     J.   Warranty provisions do not apply to Work Products delivered under the
          Development Phase of this Contract.

     K.   Contractor agrees to maintain a stock of Work Products to ship to HNS
          or it's customer in the event a Work Product is dead on arrival (DOA)
          as a loaner unit. Furthermore, Contractor agrees to ship loaner units
          to HNS or it's customer in the event that Contractor does not comply
          with the specified MTBF and HNS or it's customers spare stock is
          depleted. Shipments of Work Product in accordance with this paragraph
          are to be made via overnight delivery.

ARTICLE    QUALITY OF MATERIALS AND WORKMANSHIP

     Except as may be otherwise specifically provided in this Contract, all
Work furnished by Contractor under this Contract shall be new and free from
material defects.

ARTICLE    INSURANCE

     A.   Contractor shall procure and thereafter maintain Unemployment
          Compensation Insurance and the following other types of insurance and
          minimum coverages with respect to performance under this Contract:

          1.   Worker's Compensation Insurance in accordance with statutory
               requirements for all States in which Work is performed. This
               policy must also be endorsed to provide coverage for employees at
               the Work site who are qualified for benefits from other States
               (all States endorsement).

          2.   Employer Liability Insurance with a limit of not less than
               $1,000,000.

          3.   Comprehensive General Liability Insurance providing Operations
               Liability, Owners and Contractual Protective Liability and
               Contractual Liability (specifically, but not by way of
               limitation, covering liability assumed under the Article of this
               Contract entitled INDEMNIFICATION). Coverage is to include the
               hazards of explosion, collapse and underground damage. The policy
               shall provide a combined single limit of liability for personal
               injury (including death) and property damage for not less than
               $1,000,000 for each occurrence.

     B.   All insurance required pursuant to the provisions of this Article
          shall be in such form and with such insurers satisfactory to HNS and
          shall remain in force through HNS Acceptance or Final Acceptance
          pursuant to the Article of this Contract entitled ACCEPTANCE.
          Contractor shall file with HNS, prior to commencement of Work,
          Certificates of Insurance in evidence of the

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

          aforementioned insurance coverage. Contractor shall cause HNS,
          including, where applicable, designated owner(s) or lessor(s) of the
          Work site(s), to be named as an additional insured(s) in such general
          liability policies.

     C.   Policies offered in compliance of this Article shall provide that HNS
          shall be notified in writing by the insurer thirty (30) days in
          advance of that date upon which the insurer intends to cancel any such
          policy.

     D.   Contractor shall give HNS immediate notice of any suite or action
          filed or prompt notice of any claim made against Contractor arising
          out of the performance of this Contract. Contractor agrees to assist
          and cooperate in every manner possible in connection with the
          adjustment of all claims arising out of operations within the scope of
          Work provided for under this Contract and cooperate with the insurance
          carrier in all litigated claims and demands that the insurance carrier
          or carriers are called upon to adjust or resist, and that arise out of
          such operations.

     E.   The requirements of this Article shall be extended by Contractor to
          each of its Subcontractors performing Work at any Work site.

ARTICLE    INDEMNIFICATION

     Contractor, at it's own expense, shall indemnify and hold HNS, its
directors, officers, employees, agents, subsidiaries, affiliates, customers,
designees, and assignees harmless from any loss, damage, liability or expense,
on account of damage to property and injuries, including death, to all persons,
arising from any occurrence caused by any act or omission of Contractor or its
Subcontractors related to the performance of this Contract. Contractor, at its
expense, shall defend any suit or dispose of any claim or other proceedings
brought against said indemnities on account of such damage or injury, and shall
pay all expenses, including attorney's fees, and satisy all judgments which may
be incurred by or rendered against said indemnities

ARTICLE     RIGHTS IN DATA

     A.   All written documentation (e.g. operation manuals, maintenance
          manuals, et al) which is required to be delivered under this Contract
          or is delivered pursuant to the Article of this Contract entitled
          REPORTS shall be the exclusive property of HNS and shall not be
          disclosed to any other party, and HNS shall have the unlimited right
          to the information contained therein. HNS shall protect all other
          written documentation, which is marked by Contractor with an
          appropriate and valid proprietary legend, such as "Contractor
          Confidential," from unauthorized disclosure to any person who is not a
          director, officer, employee or agent of HNS, in the same manner as HNS
          protects its own confidential information, PROVIDED, HOWEVER, that HNS
          shall have the right to use and duplicate such written documentation
          for any HNS purpose.

     B.   Notwithstanding the foregoing, HNS shall have no obligation with
          respect to any written documentation or information previously known
          to HNS, invalidly marked, or which is or becomes in the public domain,
          or which is rightfully acquired by HNS from third parties, or which is
          independently developed by HNS, or which, is approved for release by
          the written


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

           Authorization of Contractor, or Which HNS has the Right to Disclose
           Pursuant to Any Licenses Granted Under the Article of This Contract
           Entitled PATENT RIGHTS.

ARTICLE    REPORTS

     The Contractor shall provide reports, schedule information and progress
reports as specified in the Statement of Work.

ARTICLE    HNS PROPRIETARY INFORMATION

     Contractor agrees, that with respect to any data, drawings, documents or
other writings supplied by HNS to Contractor and identified as proprietary or
HNS confidential (hereinafter referred to as "Proprietary Information"):

     1.   To use such Proprietary Information only in performance of the Work
          under this Contract;

     2.   Not to make copies of any such Proprietary Information or any part
          thereof without the written permission of HNS, or as required to
          perform the subject tasking of this contract, as limited by
          subparagraph 4 below;

     3.   To limit dissemination of such Proprietary Information to persons
          within Contractor's organization who are directly involved in the Work
          under this Contract and have a need to use such Proprietary
          Information for purposes of such Work only;

     4.   Not to disclose any such Proprietary Information or any part thereof
          to others for any purpose;

     5.   To return such Proprietary Information and any copies thereof to
          HNS, or, with prior approval from HNS, to certify destruction of all
          Proprietary Information at the completion of all Work under this
          Contract or at such earlier date as HNS may designate. However,
          Contractor may retain one copy of the Proprietary Information for
          archival purposes with HNS agreement.

ARTICLE   PATENT RIGHTS

A.   All inventions conceived or first actually reduced to practice by either
     Party under this Contract, either solely or jointly with the other Party
     and all Patents issuing thereon, shall be the joint property of the Parties
     in accordance with paragraph G of this Article. Promptly after acquiring
     knowledge of each such invention, Contractor will disclose the same to HNS
     in writing, and will provide HNS with such additional information and
     cooperation as HNS may require to secure Patent protection on the same, if
     HNS decides to seek Patent protection.

B.   With respect to other Patents not falling under Paragraph A above and only
     with respect to Work performed and Product(s) delivered under this
     Contract, Contractor hereby grants to HNS an irrevocable, nonexclusive
     license to practice and have practiced throughout the world any invention
     covered by each Patent now or hereafter owned, acquired or licensable by
     Contractor. In the event Contractor is unable or unwilling to provide Work
     or Work Products which meet


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

     the requirements of this Contract, such license shall allow HNS to make or
     have others make the items deliverable under this Contract, for use by
     HNS or for sale or lease or resale by HNS customers. Such license herein
     granted shall be (1) deemed fully paid-up only for the purpose of use,
     redesign or modification of any items delivered under this Contract, or for
     manufacture in the event Contractor is unable or unwilling to provide items
     which meet Contract requirements; and (2) on reasonable terms and
     conditions for other purposes.

C.   Any other provisions of this Contract notwithstanding, with respect to any
     inventions that any person or entity is authorized by the terms of this
     Contract to use or practice only under certain conditions or limitations,
     such use or practice shall be:

     1.   Free, unconditional and unlimited from and after the time that the
          rights in inventions come into the public domain, or

     2.   At the sole discretion of such person or entity, on other terms from
          and after the time that such rights in inventions become otherwise
          lawfully available to such person or entity on such other terms.

D.   This Article shall not be construed as limiting any rights of HNS or
     obligations of Contractor under this Contract, including specifically the
     right of HNS for no additional compensation to Contractor, to use, have
     used, deliver, lease, modify for the benefit of HNS' users, sell or
     otherwise dispose of any item or any part thereof required to be delivered
     under this Contract.

E.   Contractor shall, unless otherwise authorized or directed by HNS, include
     in each subcontract hereunder involving experimental, developmental, or
     research work or studies, a Patent Rights Article pursuant to which each
     such Subcontractor agrees to grant to HNS rights to obtain licenses under
     Patents owned or licensable by the Subcontractor to the same extent as the
     rights granted by Contractor in Paragraphs A and B above. In the event of
     refusal by a Subcontractor to accept such a Patent Rights Article,
     Contractor (1) shall promptly submit a written report to HNS setting forth
     the Subcontractor's reasons for such refusal, and (2) shall not proceed
     with the subcontract without the written authorization of HNS.

F.   Nothing in this Contract shall be construed by implication, estoppel, or
     otherwise to:

     1.   Require either Party to file any Patent application, to secure any
          Patent, or to maintain any Patent in force; or

     2.   Bring or prosecute actions or suits against third-party infringement.

G.   JOINT INVENTIONS

     1      Each Party shall have an equal, undivided one-half interest in and
     to Joint Inventions, as well as in and to patent applications and patents
     thereon in all countries. An assignment of rights in all Joint Inventions
     shall be executed in the names and for the benefit of both Endgate and
     Hughes.

     2      Endgate shall have the first right of election to file patent
     applications in any country, including the selection of the attorney or
     agent to prepare the patent application, and Hughes


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     shall have a second right of election. Each Party in turn shall make its
     election at the earliest practicable time, and shall notify the other
     Party, in writing, of its decision.

     3      The expenses for preparing, filing and securing each Joint Invention
     application, and for issuance of the respective patent shall be borne by
     the Party which prepares and files the application. The other Party shall
     furnish the filing Party with all documents or other assistance that may be
     necessary for the filing and prosecution of each application. Where such
     Joint Invention application for patent is filed by either Party in a
     country which requires the payment of taxes, annuities or maintenance fees
     on a pending application or on an issued patent, the Party which files the
     application shall, prior to filing, request the other Party to indicate
     whether it will agree to pay one-half of such taxes, annuities or
     maintenance fees. If within sixty (60) Days of receiving such request, the
     non-filing Party fails to assume in writing the obligation to pay its
     proportionate share of such taxes, annuities or maintenance fees, or if
     either Party subsequently fails to continue such payments within sixty (60)
     Days of demand, it shall forthwith relinquish to the other Party,
     providing that said other Party continues such payments, its share of the
     title to such application and patent, subject, however, to retention of a
     paid-up, non-exclusive, non-assignable license in favour of the
     relinquishing Party, its parent, and any subsidiary thereof to make, use,
     lease and sell, apparatus and/or methods under said application and patent.

     4      Endgate may sell, lease or otherwise transfer the Work, or any
     portion thereof, subject to the exclusivity, provision in the Article
     entitled STRATEGIC RELATIONSHIP, which is covered by one or more Joint
     Invention to any party provided that prior to any such sale, lease or
     transfer, Endgate agrees in writing to pay to HNS a reasonable royalty, to
     be negotiated in good faith between HNS and Endgate.

ARTICLE     PROPRIETARY RIGHTS INDEMNITY

A.   Contractor, at its own expense, shall indemnify and hold HNS, its partners,
     directors, officers, employees, agents, subsidiaries, affiliates,
     customers, designees or assignees harmless from any loss, damage, liability
     or expense on account of any claim(s), and shall defend any suit AND
     dispose of any claim(s) or other proceedings, based on an allegation that
     the manufacture of any item in the performance of this Contract, or the
     use, lease, sale or importation of any item delivered or scheduled to be
     delivered under this Contract, infringes any United States or foreign
     Patent(s), copyrights, or other proprietary right(s). Contractor shall pay
     any royalties and other costs or expenses, including attorney's fees,
     related to the defense, settlement, or disposition of such infringement
     claim(s). HNS shall promptly notify Contractor in writing of any such
     infringement claim or action and give Contractor authority and any
     assistance or information reasonably available to HNS for the defense of
     such claim(s). Any such assistance or information which is furnished by HNS
     at the request of Contractor is to be at Contractor's expense.

B.   If the manufacture of any item in the performance of this Contract, or the
     use, lease or sale of any item delivered or scheduled to be delivered under
     this Contract, is enjoined as a result of a suit based on any such claim(s)
     of infringement, Contractor agrees to utilize its best efforts (i) to
     negotiate a license or other agreement with the claimant so that the item
     is no longer subject to such injunction, or (2) to modify such item
     suitably or suitable a suitable item therefor (subject to the technical
     approval of HNS), which modified or substituted item is not subject to such


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

     injunction, and to extend the provisions of this Article thereto. In the
     event that neither of the foregoing alternatives is suitably accomplished
     by Contractor, Contractor shall be liable to HNS for HNS' additional
     costs and damages arising as a result of such injunction.

C.   Contractor agrees to use its best efforts to design, develop and
     manufacture the items to be delivered under this Contract so that the
     manufacture, use, lease, sale or importation of any such items shall not
     infringe any United States or foreign Patent(s) or other proprietary
     right(s). Contractor further agrees to use its best efforts to identify and
     promptly report to HNS any unexpired Patents or other proprietary
     rights of third parties which may be infringed by the manufacture, use,
     lease, sale or importation of any item delivered under this Contract.

D.   HNS neither represents nor warrants that the performance of any Work or the
     manufacture, use, lease or sale of any deliverable item will be free from
     any third-party claim(s) of infringement of any United States or foreign
     Patent(s) or other proprietary right(s).

ARTICLE   EXCUSABLE DELAY

     Acts of God, or of the public enemy, acts of the Government in its
sovereign capacity, fires, floods, strikes, epidemics, quarantine restrictions,
freight embargoes and failure of HNS to deliver HNS-furnished property as
required under this Contract, which cause failure to perform hereunder and, in
every case, are beyond the reasonable control and without the fault or
negligence of Contractor, shall constitute an excusable delay, if written notice
thereof is given to HNS within twenty (20) days after such event shall have
occurred. In the event of delay resulting from any of the above causes, only the
applicable delivery requirements will be extended accordingly. In the event
that an excusable delay should occur and go beyond ninety (90)days, HNS has the
right to terminate this Contract without liability.

ARTICLE   CHANGES

     A.   HNS may, with mutual agreement of Contractor which agreement will not
          be unreasonably withheld, by written change order, and without notice
          to any surety, make changes within the general scope of this Contract
          in drawings, designs, specifications, methods of shipment or
          packaging/packing, quantities, or time or place of delivery require
          additional Work; or direct the omission of Work. If any such change
          causes an increase or decrease in the cost of, or the time required
          for performance of, this Contract, an equitable adjustment shall be
          made in the price(s), or delivery date(s), or both, and this Contract
          shall be amended in writing accordingly. Any claim for adjustment by
          Contractor under this Paragraph shall be deemed waived unless asserted
          in writing within thirty (30) days from the date of receipt by
          Contractor of the change order. The amount of such claim shall be
          stated either when it is submitted, or at such later date not to
          exceed sixty (60) days from the date of assertion of the claim. Such
          later date shall be requested at the time of submission of such claim
          by Contractor. If the cost of supplies or materials made obsolete or
          excess as a result of a change is included in Contractor's claim for
          adjustment, HNS shall have the right to prescribe the manner and means
          of their disposition and shall be entitled to the proceeds, if any of
          such disposition. Nothing in this Article shall excuse Contractor from
          promptly proceeding with this Contract as changed. Changes to this
          Contract can only be made by a duly authorized representative of the
          HNS Procurement Department.


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                                                           SUBCONTRACT AGREEMENT
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     B.   If Contractor or HNS claims a right to adjustment pursuant to
          Paragraph A of this Article, Contractor shall prepare and furnish to
          HNS the evidence necessary to establish the amount of any increase
          or decrease in the cost of, or the time required for, the performance
          of this Contract caused by the change order. Subject to Paragraph D of
          this Article, the amount of any such change increase or decrease shall
          be determined in accordance with the Contractor's regularly
          established accounting practices and shall, if requested by HNS, be
          verified by an independent Certified Public Accounting firm.

     C.   The Parties shall attempt to reach agreement as to any equitable
          adjustment that is due pursuant to Paragraph A of this Article.
          Without relieving Contractor of its obligation to proceed promptly
          with this Contract as changed, in the event the Parties are unable to
          reach agreement as to an equitable adjustment, the matter shall be
          determined in accordance with the Article entitled ARBITRATION.

     D.   HNS' personnel may from time to time render technical assistance or
          give technical advice to, or effect an exchange of information with,
          Contractor personnel concerning the Work to be furnished under this
          Contract. However, Contractor shall not deviate from the requirements
          of this Contract by reason of such assistance or exchange of
          information, unless the deviation is incorporated into and authorized
          by a change order issued in accordance with Paragraph A of this
          Article. The Contractor shall not, by reason of such assistance,
          advice or exchange of information, delete or in any way modify any of
          HNS' rights or any of Contractor's obligations, express or implied,
          which are a part of this Contract.

ARTICLE   TERMINATION FOR CONVENIENCE

     A.   By written notice to Contractor, HNS may terminate this Contract, in
          whole or in part, for its convenience at any time prior to completion.
          In the event of such termination by HNS, it is agreed that the
          termination charges shall be negotiated. However, in no event shall
          the termination charges pursuant to this Article exceed the lesser of:

          1.   The total Contract price as reduced by the Contract price of Work
               not terminated; or

          2.   For the Development Phase, HNS shall reimburse Contractor for
               the costs accrued to and including the milestone of the
               Development Phase at which the Contract is terminated. HMS
               shall, however, not have the right to terminate the Contract
               until after milestone l(Minimum level) as stated in the Article
               entitled Price And Payment, paragraph C; or

          3.   For the Production Phase, if any, [*] of the total manufacturing
               costs (exclusive of nonrecurring engineering costs), both direct
               and it. direct, incurred by Contractor in the performance of the
               Work so terminated.

     B.   In the event of termination pursuant to this Article, Contractor shall
          take all action, necessary to reduce the termination costs due from
          HNS, including, but not limited to, the immediate discontinuance of
          the terminated Work under this Contract, and the placing of no further
          orders for labor, material or services required under the terminated
          portion. Contractor agees to take

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

          such action as may be necessary, or as HNS may direct, for protection
          of property in Contractor's possession in which HNS may have acquired
          an interest.

     C.   Contractor shall continue performance of the portion of this Contract
          not terminated. HNS shall have no obligations to Contractor with
          respect to the terminated portion of this Contract, except as herein
          provided.

     D.   Contractor agrees to advise HNS in writing of all proposed
          settlements with vendors in the event of termination, and Contractor
          further agrees not to enter into any binding settlement until either
          HNS has approved the proposed settlement or thirty (30) days have
          elapsed from the date HNS was first notified of such
          proposed settlement.

     E.   Direct and indirect costs shall be determined in accordance with
          generally accepted accounting practices and verified by an independent
          Certified Public Accountant. HNS shall pay Contractor the termination
          charges due under this Article within sixty (60) days after submission
          to HNS of such total costs certified by the independent Certified
          Public Accountant. Payment of any termination charges hereunder shall
          be in an amount equal to the total termination charges less the
          following:

          1.   Amount(s) previously paid by HNS to Contractor for the terminated
               Work pursuant to this Contract; and

          2.   Amount(s) representing Contractor's total cost of segregable
               items of inventory for the terminated Work not desired by HNS
               and which Contractor elects to retain for its use.

          Should the sum of (1) and (2) above exceed the total termination
          charges, Contractor shall repay to HNS within sixty (60) days the
          amount by which the sum of (l) and (2) above exceed the total
          termination charges.

     F.   In the event of such TERMINATION, all inventory for the terminated
          Work, including, but not limited to, the Work Product of Contractor
          generated under this Contract, other than as specified in Paragraph E2
          of this Article, shall become the property of HNS.

ARTICLE   TERMINATION FOR DEFAULT

     A.   By written notice of default to Contractor, HNS may terminate this
          Contract, in whole or in part, in any one of the following
          circumstances:

          1.   If Contractor fails to make delivery of the Work within the time
               specified herein or any extension thereof; or

          2.   If Contractor fails to perform any of the provisions of this
               Contract, or so fails to make progress as to endanger performance
               of this Contract in accordance with its terms, and in either of
               these two circumstances does not cure such failure within a
               period of twenty (20) days (or such longer period as HNS may
               authorize in writing) after receipt of notice from HNS specifying
               such failure; or


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

          3.   The Contractor becomes insolvent or the subject of proceedings
               under any law relating to bankruptcy or the relief of debtors or
               admits its inability to pay its debts as they become due.

     B.   In the event of default under this Article, Contractor shall repay to
          HNS any payments made by HNS in excess of the price of Work delivered
          by Contractor and accepted by HNS. In no event shall HNS be liable for
          the cost of completed Work not delivered and accepted by HNS.

     C.   In the event HNS terminates this Contract, in whole or in part, as
          provided in Paragraph A of this Article, HNS may procure, upon such
          terms and in such manner as HNS may deem appropriate, Work similar to
          that so terminated, and Contractor shall be liable to HNS for any
          excess costs(which HNS will make reasonable efforts to limit)for such
          similar Work [*], PROVIDED, HOWEVER, that Contractor shall continue
          performance of this Contract to the extent not terminated under the
          provisions of this Article.

     D.   If this Contract is terminated as provided in Paragraph A of this
          Article, in addition to any other rights provided in this Article, HNS
          may require Contractor to transfer title and deliver to HNS in the
          manner and to the extent directed by HNS, (1) any completed supplies,
          and (2) such partially completed supplies and materials, parts, tools,
          dies, jigs, fixtures, and contract rights (hereinafter called
          "Manufacturing Materials") as Contractor has specifically produced or
          specifically acquired for the performance of such part of this
          Contract as has been terminated, and Contractor shall, upon direction
          of HNS, protect and preserve property in the possession of
          Contractor in which HNS has an interest. Payment for completed
          supplies delivered to and accepted by HNS shall be at the price stated
          in this Contract. Payment for Manufacturing Materials delivered to and
          accepted by HNS, and for the protection and preservation of property,
          shall be in an amount agreed upon by Contractor and HNS; failure to
          agree on such amount shall be a dispute within the meaning of the
          Article of this Contract entitled ARBITRATION. HNS may withhold from
          amounts otherwise due Contractor for such completed supplies or
          Manufacturing Materials, such sum(s) as HNS deems necessary to protect
          HNS against any loss arising in connection with outstanding liens or
          claims of former lien holders.

     E.   If, after notice of termination of this Contract under the provisions
          of this Article, it is determined for any reason that Contractor was
          not in default under the provisions of this Article, or that the
          default was excusable under the provisions of the Article of this
          Contract entitled EXCUSABLE DELAYS, the rights and obligations of the
          Parties shall be the same as if the notice of termination had been
          issued pursuant to the Article of this Contract entitled TERMINATION
          FOR CONVENIENCE.

     F.   The rights and remedies of HNS, provided in this Article, include the
          right to recovery of attorney's fees, and are not exhaustive and are
          in addition to any other rights and remedies under this Contract or by
          operation of law.

ARTICLE   ESCROW OF DESIGN RIGHTS AND DOCUMENTATION

     Contractor shall deposit in an Escrow account, to be mutually agreed to,
all pertinent drawings, documentation, test procedures, artwork, design data,
including but not limited to source source code and/or other software, necessary
to manufacture, test, use, support and sell the Product(s) at the earliest
possible time after generation of such drawings, documents, design data and
software, but no later than


[*] CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

20 days after its generation. The right to utilize and manufacture, without
cost, such drawings, documentation, artwork, design data, including but not
limited to software source code and/or other software will convey to HNS as
provided for in the Article of this Contract entitled RIGHTS TO MANUFACTURE.
This right or remedy shall be in addition to any other rights or remedies
provided by law.

ARTICLE    RIGHTS TO MANUFACTURE

     HNS, at its sole option, may request and Contractor shall provide all
pertinent and required documentation, including software, artwork, test
procedures, specifications, parts lists, drawings, etc., as escrowed pursuant to
the Article of this Contract entitled ESCROW OF DESIGN RIGHTS AND DOCUMENTATION,
necessary for HNS to manufacture or have manufactured, test, support, use, sell
and resell the Product(s) should any of the circumstances listed in the Article
of this Contract TERMINATION FOR DEFAULT occur or in the event this Contract is
terminated under the provisions of the Article of this Contract TERMINATION FOR
DEFAULT.

     Further, the right to manufacture shall be granted as a non-exclusive,
worldwide, unrestricted, non-transferable, royalty free right to HNS. Contractor
shall also provide reasonable consultation of its key personnel at no cost to
HNS other than the reasonable and actual travel and living costs should HNS
require any travel.

ARTICLE         LIQUIDATED DAMAGES

     A.   The Parties hereto agree that timely performance is a primary
          consideration in this Contract, and, therefore, it is agreed that time
          is of the essence hereunder.

     B.   Following an initial grace period of thirty (30) calendar days of
          delay, for each calendar week of delay thereafter, up to a maximum of
          ten (10) calendar weeks, following the required delivery date(s)
          Contractor shall pay to HNS as fixed, agreed and liquidated damages,
          and not as a penalty, for said delay, [*] per week of the Purchase
          Order value.

     C.   Any amount(s) Contractor owes to HNS, pursuant to the provisions of
          this Article, may be deducted by HNS from Contractor's invoice(s)or
          other surety if any.

     D.   If Contractor does not fully demonstrate that the Work meets the
          requirements of this Contract, and HNS does not exercise its right
          to terminate this Contract for default in accordance with the Article
          of this Contract entitled TERMINATION FOR DEFAULT, the liquidated
          damages in this Article shall be the sole compensation to which HNS
          shall be entitled for delays for the number of days stated in
          Paragraph B of this Article provided, however, that damages incurred
          by HNS after said period of delay for which liquidated damages are
          recovered shall be as at law or as otherwise provided in this
          Contract.

     E.   As used in this Article, "Calendar Days" or "Calendar Weeks" shall
          mean part of a day or week commencing at twelve (12) o'clock midnight,
          EST.

[*]  CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY WITH
     THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
     THE OMITTED PORTIONS.


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                                                           SUBCONTRACT AGREEMENT
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ARTICLE    ARBITRATION

     If any dispute or disagreement arising between Contractor and HNS in
connection with this Contract cannot be settled to the mutual satisfaction of
Contractor and HNS within thirty (30) days (or such longer period as may be
mutually agreed upon) from the date that either Party informs the other in
writing that such dispute or disagreement exists, the parties shall submit such
disputes to binding arbitration. Within thirty (30) days after either party has
notified the other in writing that it is submitting a dispute to arbitration,
one arbitrator shall be selected under the then current rules of the American
Arbitration Association ("AAA") pertaining to commercial disputes and shall be
held in Washington, D.C. The arbitration shall be conducted in accordance with
the Commercial Arbitration rules of the AAA, except the AAA shall not have
authority to make any award for damages excluded herein. The arbitration award
shall be by a written decision and shall be final and binding and enforceable by
any court of competent jurisdiction. Either party may seek appropriate
injunctive relief in any court of competent jurisdiction.

ARTICLE    CONTRACTOR'S RESPONSIBILITY

     A.   Contractor is an independent contractor and is responsible to HNS
          for all acts and omissions of all persons directly or indirectly used
          by it or any of its subcontractor(s), unless a subcontractor is
          designated by HNS, in connection with the Work required by this
          Contract, PROVIDED, HOWEVER, that nothing in this Contract shall be
          construed as creating any contractual relationship between HNS and
          any subcontractor.

     B.   The granting of any approvals by HNS shall not affect the
          responsibility of Contractor for the design of the Work to meet
          Contract requirements or for the correctness of Contractor's drawings
          and specifications. No such granting by HNS or course of dealing
          between the Parties shall be held to constitute a waiver by HNS of any
          of HNS rights under this Contract. All waivers by HNS shall be in
          writing.

ARTICLE        TRADE NAMES, TRADEMARKS AND TRADE DRESS

     A.   Contractor agrees to comply with all HNS instructions regarding the
          trade dress packaging, trade names, trademarks, service marks or other
          indicia of source which shall appear on items to be delivered under
          this Contract. Contractor further agrees that, after delivery of said
          item(s) to HNS or a designated HNS customer, HNS may modify the trade
          dress or packaging thereof, and/or replace, modify, or supplement any
          indicia of origin appearing thereon, to identify HNS as the source of
          said item(s).

     B.   Neither Party shall use any mark or trade name of the other Party or
          refer to the other Party in connection with any product, equipment,
          promotion, or publication without the prior written approval of the
          other Party.


                                       18
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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE    PUBLIC RELEASE OF INFORMATION

     Contractor shall obtain the prior written approval of HNS concerning the
content and timing of news releases, articles, brochures, advertisements,
speeches and other information releases concerning the Work performed or to be
performed hereunder by Contractor, its Subcontractor(s) or employee(s) or
consultant(s) of either. Contractor agrees to give HNS reasonable advance time
for review of any material submitted to HNS for approval.

ARTICLE   NOTICES

     Any notice(s) required or permitted to be given or made in this Contract
shall be in writing. Such notice(s) shall be deemed to be duly given or made
when it shall have been delivered by facsimile transmission [FAX], hand, or
registered mail to the Party to which it is required to be given or made at such
Party's address specified below:

       HNS:       Hughes Network Systems, Inc.
                  11717 Exploration Lane
                  Germantown, Maryland 20876
       Attn:      John Grimes


                  Purchasing Agent


                  TEL (301) 548-8401
                  FAX (301) 548-8458

      Contractor: Endgate Corporation
                  321 Soquel Way
                  Sunnyvale, CA 94086
      Attn:       Julianne Marie Biagini
                  TEL (408) 737-7300
                  FAX (408) 737-6794

ARTICLE   ORDER OF PRECEDENCE

     In the event of any ambiguity and/or inconsistency between the Terms and
Conditions, Statement of Work, Specifications, Drawings or other documents
incorporated by reference, the following descending order of precedence shall
control:

     1.   Terms and Conditions and any amendments thereto;

     2.   Exhibit A, Statement of Work Revision 6 and dated March 18, 1998;

     3.   Exhibit B, Performance Requirements Specification 1024668 and 1025231
          at their current revision;

     4.   Purchase Order(s);

     5.   Drawings and other documents attached to the Specifications or
          incorporated by reference.


                                       19
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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE   APPLICABLE LAW

     This Contract shall be interpreted, construed and governed by the laws of
the State of Maryland.

ARTICLE   GENERAL

     A.   Contractor agrees that the Work performed under this Contract,
          including the Products and services of that Work, shall comply with
          all applicable permits and licenses and the requirements ofal
          applicable laws, regulations and standards as required by the
          Statement Of Work.

     B.   Where this Contract or any code, ordinance, or governmental regulation
          requires a material or item to conform to a particular standard,
          Contractor shall, at the request of HNS, deliver to HNS a certificate
          from the manufacturer or its authorized representative stating that
          the material or item furnished conforms to the standard prescribed.
          Such certificate shall be in triplicate and in such form as HNS may
          require.

     C.   Contractor agrees that it will neither incorporate any provision in
          its subcontracts nor enter into any agreement, written or oral, either
          directly or indirectly, with Subcontractors or vendors which has or
          may have the effect of prohibiting Subcontractor or vendor sales
          directly to HNS of any supplies like those manufactured or services
          like those furnished, by any tier Subcontractor or vendor pursuant to
          this Contract.

     D.   Neither Party shall assign or delegate this Contract or any of its
          rights, duties or obligations thereunder to any person or entity
          without the prior written approval of the other Party.

     E.   All documentation, notices, reports and correspondence under this
          Contract shall be submitted and maintained in the English language.

ARTICLE   EXAMINATION OF CONTRACT

     A.   By executing this Contract, the Parties represent that they have
          thoroughly examined this Contract and believe it to be complete,
          consistent and accurate.

     B.   The terms of this Contract constitute the final and entire agreement
          between the Parties, and no prior or contemporaneous representations,
          expressions or agreements, either written or oral, shall vary or
          supplement the terms of this Contract. The terms of this Contract
          shall not be supplemented or contradicted by course of dealing, usage
          of trade or course of performance under this or other contracts.

     C.   Amendments to this Contract shall be in writing and signed by both
          Parties.


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                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE   PRODUCT SUPPORT

     A.   The Contractor warrants that the items purchased under this Order,
          including subassemblies and spare parts, shall be available to HNS and
          its customers during the operational life of the items purchased or
          fifteen (15) years after the date of final shipment under this Order,
          whichever is later.

     B.   In the event the Contractor discontinues manufacture of the
          aforementioned items, subassemblies and spare parts therefore and does
          not provide for another qualified source, the Contractor shall make
          available to HNS all drawings, specifications, data, etc., which will
          enable HNS or its customers to manufacture or procure said items,
          subassemblies and spare parts under a royalty-free license which is
          hereby granted.

     C.   The Contractor shall support the items purchased hereunder during the
          operational life of the items or for a period of fifteen (15) years
          from the date of final shipment under this Order. Said support
          includes, but is not limited to, technical services and maintenance of
          Contractor's stock of subassemblies and spare parts as may be required
          to be ordered to support the operation of the items.

ARTICLE   KEY PERSONNEL

Contractor represents and warrants to HNS that the services of certain key
personnel, specifically John Mikulsky, Dick Mayeur, Dan Teuthorn, Jim Wilfong,
Bryson Wallace and Ray Biasing and the Key Personnel Retention Plan (Exhibit C)
will be applied to the performance of this Contract during the Development Phase
and HNS has relied on this representation and warranty as a material
inducement to entering into this Contract. Accordingly, should the services of
John Mikulsky, Dick Mayeur, Dan Teuthorn, Jim Wilfong, Bryson Wallace and Ray
Blasing cease to be applied to the performance of this Contract, Contractor and
HNS will promptly confer and if Contractor does not demonstrate within ten
(10) business days to HNS's reasonable satisfaction the substitution of an
alternate individual of equal or greater knowledge, skill, experience and
judgement, HNS may declare Contractor in default pursuant to the provisions of
the Article TERMINATION FOR DEFAULT. Contractor shall notify HNS of any
material changes to the Key Personnel Retention Plan as shown in Exhibit C
attached hereto which is deliverable to HNS within ten (10) working days of
execution of this Contract.


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<PAGE>


                                                           SUBCONTRACT AGREEMENT
                                                                8050025 (12/93P)

ARTICLE    SURVIVAL

The provisions of this Contract that by their sense and context are intended to
survive the termination of this Contract shall so survive.


IN WITNESS WHEREOF, the Parties hereto have executed this Contract.


                                                 HUGHES NETWORK SYSTEMS

ATTEST:                                          BY: /s/ Suresh Arora
       ---------------------------------            ---------------------------
                                                 NAME: /s/ Suresh Arora
                                                      -------------------------
                                                 TITLE: Vice President
                                                       ------------------------

                                                 ENDGATE CORPORATION

ATTEST: /s/ JULIANNE M. BIAGINI                  BY: /s/ James Bybokas
       ---------------------------------            ---------------------------
                                                 NAME: James Bybokas
                                                      -------------------------
                                                 TITLE: Vice President
                                                       ------------------------


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