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                                                                    EXHIBIT 10.8

[CB RICHARD ELLIS LOGO]

                                    SUBLEASE

1.   PARTIES.

     This sublease, dated SEPTEMBER 24, 2002, is made between WESTERN
     TECHNOLOGY ("Sublessor"), and CATAPULT COMMUNICATIONS ("Sublessee").

2.   MASTER LEASE.

     Sublessor is the lessee under a written lease dated MARCH 25, 1995 wherein
     JACK DYMOND LATHING CO. ("Lessor") leased to Sublessor the real property
     located in the City of Mountain View, County of SANTA CLARA, State of
     CALIFORNIA, described as 190 S. WHISMAN ROAD, BUILDING G. ("Master
     Premises"). Said lease has been amended by the following amendments FIRST
     AMENDMENT DATED APRIL 24, 2000 AND SECOND AMENDMENT DATED AUGUST 22, 2000:
     said lease and amendments are herein collectively referred to as the
     "Master Lease" and are attached hereto as Exhibit "A".

3.   PREMISES.

     Sublessor hereby subleases to Sublessee on the terms and conditions set
     forth in this Sublease the following portion of the Master Premises
     ("Premises"): THAT APPROXIMATELY 9,860 SQUARE FOOT FREESTANDING INDUSTRIAL
     BUILDING LOCATED AT 190 S. WHISMAN ROAD, BUILDING G, MOUNTAIN VIEW, CA
     94041.

4.   WARRANTY BY SUBLESSOR.

     Sublessor warrants and represents to Sublessee that the Master Lease has
     not been amended or modified except as expressly set forth herein, that
     Sublessor is not now, and as of the commencement of the Term hereof will
     not be, in default or breach of any of the provisions of the Master Lease,
     and that Sublessor has no knowledge of any claim by Lessor that Sublessor
     is in default or breach of any of the provisions of the Master Lease.

5.   TERM.

     The Term of this Sublease shall commence on DECEMBER 1, 2002
     ("Commencement Date"), or when Lessor consents to this Sublease (if such
     consent is required under the Master Lease), whichever shall last occur,
     and end on FEBRUARY 28, 2005 ("Termination Date"), unless otherwise sooner
     terminated in accordance with the provisions of this Sublease. In the
     event the Term commences on a date other than the Commencement Date,
     Sublessor and Sublessee shall execute a memorandum setting forth the
     actual date of commencement of the Term. Possession of the Premises
     ("Possession") shall be delivered to Sublessee UPON COMPLETE EXECUTION OF
     THE SUBLEASE. If for any reason Sublessor does not deliver Possession to
     Sublessee on the commencement of the Term, Sublessor shall not be subject
     to any liability for such failure, the Termination Date shall not be
     extended by the delay, and the validity of this Sublease shall not be
     impaired, but rent shall abate until delivery of Possession.
     Notwithstanding the foregoing, if Sublessor has not delivered Possession
     to Sublessee within thirty (30) days after the Commencement Date, then at
     any time thereafter and before delivery of Possession, Sublessee may give
     written notice to Sublessor of Sublessee's intention to cancel this
     Sublease. Said notice shall set forth an effective date for such
     cancellation which shall be at least ten (10) days after delivery of said
     notice to Sublessor. If Sublessor delivers Possession to Sublessee on or
     before such effective date, this Sublease shall remain in full force and
     effect. If Sublessor fails to deliver Possession to Sublessee on or before
     such effective date, this Sublease shall be cancelled, in which case all
     consideration previously paid by Sublessee to Sublessor on account on this
     Sublease shall be returned to Sublessee, this Sublease shall thereafter be
     of no further force or effect, and Sublessor shall have no further
     liability to Sublessee on account of such delay or cancellation. If
     Sublessor permits Sublessee to take Possession prior to the commencement
     of the Term, such early Possession shall not advance the Termination Date
     and shall be subject to the provisions of this Sublease.

6.   RENT.

     6.1  Minimum Rent.  Sublessee shall pay to Sublessor as minimum rent,
          without deduction, setoff, notice, or demand, at WESTERN TECHNOLOGY,
          315 DIGITAL DRIVE, MORGAN HILL, CA 95037 or at such other place as
          Sublessor shall designate from time to time by notice to Sublessee,
          the sum of FIVE THOUSAND ONE HUNDRED TWENTY-SEVEN AND 20/100 Dollars
          ($5,127.20) per month, in advance on the first day of each month of
          the Term.  Sublessee shall pay to Sublessor upon execution of this
          Sublease the sum of FIVE  THOUSAND ONE HUNDRED TWENTY-SEVEN AND 20/100
          Dollars ($5,127.20) as rent for DECEMBER 2002. If the Term begins or
          ends on a day other than the first or last day of a month, the rent
          for the partial months shall be prorated on a per diem basis.
          Additional provisions:  N/A

     6.2  Operating Costs. If the Master Lease requires Sublessor to pay to
          Lessor all or a portion of the expenses of operating the building
          and/or project of which the Premises are a part ("Operating Costs"),
          including but not limited to taxes, utilities, or insurance, then
          Sublessee shall pay to Sublessor as additional rent ONE HUNDRED
          PERCENT (100%) of the amounts payable by Sublessor for Operating Costs
          incurred during the Term. Such additional rent shall be payable as and
          when Operating Costs are payable by Sublessor to Lessor. It the Master
          Lease provides for the payment by Sublessor of Operating Costs on the
          basis of an estimate thereof, then as and when adjustments between
          estimated and actual Operating Costs are made under the Master Lease,
          the obligations of Sublessor and Sublessee hereunder shall be adjusted
          in a like manner; and if any such adjustment shall occur after the
          expiration or earlier termination of the Term, then the obligations of
          Sublessor and Sublessee under this Subsection 6.2 shall survive such
          expiration or


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     termination. Sublessor shall, furnish Sublessee with copies of all
     statements submitted by Lessor of actual or estimated Operating Costs
     during the Term.

7.   SECURITY DEPOSIT.

     Sublessee shall deposit with Sublessor upon execution of this Sublease the
     sum of FIVE THOUSAND AND NO/100 DOLLARS ($5,000.00) as security for
     Sublessee's faithful performance of Sublessee's obligations hereunder
     ("Security Deposit"). If Sublessee fails to pay rent or other charges when
     due under this Sublease, or fails to perform any of its other obligations
     hereunder, Sublessor may use or apply all or any portion of the Security
     Deposit for the payment of any rent or other amount then due hereunder and
     unpaid, for the payment of any other sum for which Sublessor may become
     obligated by reason of Sublessee's default or breach, or for any loss or
     damage sustained by Sublessor as a result of Sublessee's default or breach.
     If Sublessor so uses any portion of the Security Deposit, Sublessee shall,
     within ten (10) days after written demand by Sublessor, restore the
     Security Deposit to the full amount originally deposited, and Sublessee's
     failure to do so shall constitute a default under this Sublease. Sublessor
     shall not be required to keep the Security Deposit separate from its
     general accounts, and shall have no obligation or liability for payment of
     interest on the Security Deposit. In the event Sublessor assigns its
     interest in this Sublease, Sublessor shall deliver to its assignee so much
     of the Security Deposit as is then held by Sublessor. Within ten (10) days
     after the Term has expired, or Sublessee has vacated the Premises, or any
     final adjustment pursuant to Subsection 6.2 hereof has been made, whichever
     shall last occur, and provided Sublessee is not then in default of any of
     its obligations hereunder, the Security Deposit, or so much thereof as had
     not theretofore been applied by Sublessor, shall be returned to Sublessee
     or to the last assignee, if any, of Sublessee's interest hereunder.

8.   USE OF PREMISES.

     The Premises shall be used and occupied only for SERVICE CENTER, LIGHT
     MANUFACTURING, RESEARCH AND DEVELOPMENT, STORAGE AND OTHER RELATED LEGAL
     USES, and for no other use or purpose.

9.   ASSIGNMENT AND SUBLETTING.

     Sublessee shall not assign this Sublease or further sublet all or any part
     of the Premises without the prior written consent of Sublessor (and the
     consent of Lessor, if such is required under the terms of the Master
     Lease).

10.  OTHER PROVISIONS OF SUBLEASE.

     All applicable terms and conditions of the Master Lease are incorporated
     into and made a part of this Sublease as if Sublessor the lessor
     thereunder, Sublessee the lessee thereunder, and the Premises the Master
     Premises, except for the following: N/A. Sublessee assumes and agrees to
     perform the lessee's obligations under the Master Lease during the Term to
     the extent that such obligations are applicable to the Premises, except
     that the obligation to pay rent to Lessor under the Master Lease shall be
     considered performed by Sublessee to the extent and in the amount rent is
     paid to Sublessor in accordance with Section 6 of this Sublease. Sublessee
     shall not commit or suffer any act or omission that will violate any of the
     provisions of the Master Lease, Sublessor shall exercise due diligence in
     attempting to cause Lessor to perform its obligations under the Master
     Lease for the benefit of Sublessee. If the Master Lease terminates, this
     Sublease shall terminate and the parties shall be relieved of any further
     liability or obligation under this Sublease, provided however, that if the
     Master Lease terminates as a result of a default or breach by Sublessor or
     Sublessee under this Sublease and/or the Master Lease, then the defaulting
     party shall be liable to the nondefaulting party for the damage suffered as
     a result of such termination. Notwithstanding the foregoing, if the Master
     Lease gives Sublessor any right to terminate the Master Lease in the event
     of the partial or total damage, destruction, or condemnation of the Master
     Premises or the building or project of which the Master Premises are a
     part, the exercise of such right by Sublessor shall not constitute a
     default or breach hereunder.

11.  ATTORNEY'S FEES.

     If Sublessor, Sublessee, or Broker shall commence an action against the
     other arising out of or in connection with this Sublease, the prevailing
     party shall be entitled to recover its costs of suit and reasonable
     attorney's fees.

12.  AGENCY DISCLOSURE:

     Sublessor and Sublessee each warrant that they have dealt with no other
     real estate broker in connection with this transaction except: CB RICHARD
     ELLIS, INC., who represents CATAPULT COMMUNICATIONS and CB RICHARD ELLIS,
     INC. who represents WESTERN TECHNOLOGY. In the event CB RICHARD ELLIS,
     INC., represents both Sublessor and Sublessee, Sublessor and hereby confirm
     that they were timely advised of the dual representation and that they
     consent to the same, and that they do not expect said broker to disclose to
     either of them the confidential information of the other party.

13.  COMMISSION:

     Upon execution of this Sublease, and consent thereto by Lessor (if such
     consent is required under the terms of the Master Lease), Sublessor shall
     pay Broker a real estate brokerage commission in accordance with
     Sublessor's contract with Broker for the subleasing of the Premises, if
     any, and otherwise in the amount of
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     FOUR THOUSAND AND NO/100 Dollars ($4,000.00), for services rendered in
     effecting this Sublease. Broker is hereby made a third party beneficiary of
     this Sublease for the purpose of enforcing its right to said commission.

14.  NOTICES:

     All notices and demands which may or are to be required or permitted to be
     given by either party on the other hereunder shall be in writing. All
     notices and demands by the Sublessor to Sublessee shall be sent by United
     States Mail, postage prepaid, addressed to the Sublessee at the Premises,
     and to the address herein below, or to such other place as Sublessee may
     from time to time designate in a notice to the Sublessor. All notices and
     demands by the Sublessee to Sublessor shall be sent by United States Mail,
     postage prepaid, addressed to the Sublessor at the address set forth
     herein, and to such other person or place as the Sublessor may from time to
     time designate in a notice to the Sublessee.

     To Sublessor: WESTERN TECHNOLOGY, ATTN: NORM WILLIAMS, 315 DIGITAL DRIVE,
                   MORGAN HILL, CA 95037

     To Sublessee: CATAPULT COMMUNICATIONS, 160 S. WHISMAN DRIVE,
                   MOUNTAIN VIEW, CA 94041

15. CONSENT BY LESSOR.

    THIS SUBLEASE SHALL BE OF NO FORCE OR EFFECT UNLESS CONSENTED TO BY LESSOR
    WITHIN 10 DAYS AFTER EXECUTION HEREOF, IF SUCH CONSENT IS REQUIRED UNDER THE
    TERMS OF THE MASTER LEASE.

16. COMPLIANCE.

    The parties hereto agree to comply with all applicable federal, state and
    local laws, regulations, codes, ordinances and administrative orders having
    jurisdiction over the parties, property or the subject matter of this
    Agreement, including, but not limited to, the 1964 Civil Rights Act and all
    amendments thereto, the Foreign Investment in Real Property Tax Act, the
    Comprehensive Environmental Response Compensation and Liability Act, and The
    Americans With Disabilities Act.

Sublessor: WESTERN TECHNOLOGY                 Sublessee: CATAPULT COMMUNICATIONS

By:        /s/ NORM WILLIAMS                             By: /s/ DAVID MAYFIELD
    -------------------------                                -------------------
         NORM WILLIAMS                                           DAVID MAYFIELD

Title: PRESIDENT                                         Title: PRESIDENT & COO
       ----------------------                                   ----------------

By:                                                      By:    David Mayfield
    -------------------------                                -------------------

Title:                                                   Title: President & COO
       ----------------------                                   ----------------

Date:       9/30/02                                      Date:       9/30/02
      -----------------------                                  -----------------

                          LESSOR'S CONSENT TO SUBLEASE

The undersigned ("Lessor"), lessor under the Master Lease, hereby consents to
the foregoing Sublease without waiver of any restriction in the Master Lease
concerning further assignment or subletting. Lessor certifies that, as of the
date of Lessor's execution hereof, Sublessor is not in default or breach of any
of the provisions of the Master Lease, and that the Master Lease has not been
amended or modified except as expressly set forth in the foregoing Sublease.


Lessor: JACK DYMOND LATHING CO.
        -----------------------

By: /s/ BETTY SEMICH
    ---------------------------

Title: Member
       ------------------------

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CONSULT YOUR ADVISORS - This document has been prepared for approval by your
attorney. No representation or recommendation is made by Broker as to the legal
sufficiency or tax consequences of this document or the transaction to which it
relates. These are questions for your attorney.

In any real estate transaction, it is recommended that you consult with a
professional, such as a civil engineer, industrial hygienist or other person,
with experience in evaluating the condition of the property, including the
possible presence of asbestos, hazardous materials and underground storage
tanks.
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                                  ATTACHMENT A

          ADDENDUM TO THE SUBLEASE AGREEMENT DATED SEPTEMBER 24, 2002
              BETWEEN WESTERN TECHNOLOGY (SUBLESSOR) AND CATAPULT
                           COMMUNICATIONS (SUBLESSEE)

In the event of express conflict between the terms and conditions of this
Attachment and the terms and conditions of the Sublease, the terms and
conditions of this Attachment shall prevail.

17) Early Occupancy:          Upon execution of the Sublease and consent by
                              Landlord, Sublessee shall have the access to the
                              Premises for the purpose of completing Tenant
                              Improvements, set up phone lines, other equipment
                              and to conduct normal business operations free of
                              any and all rents.

18) Furniture & Equipment:    The Sublessor shall remove all existing furniture
                              and phone equipment. However, all existing wiring
                              shall remain in place.

19) Signage:                  Sublessee, at Sublessee's sole cost and expense,
                              will be allowed to install signage in accordance
                              with conditions of the Master Lease and subject to
                              the City of Mountain View approval.

20) Tenant Improvements:      Sublessee shall be allowed to complete Tenant
                              Improvements in accordance with the Master Lease.

21) Condition of Premises:    Sublessor shall deliver the Premises in good,
                              clean, working condition, Sublessee shall sublease
                              the space in "AS-IS" condition.

22) Sublease:                 Sublessee shall have the right to transfer or
                              assign the sublease and sub-sublease all or part
                              of the premises, with consent of the Landlord,
                              pursuant to the terms and conditions of the Master
                              Lease. Should Sublessee derive a profit from any
                              sub-sublease, Sublessee shall split the profits
                              50/50 with Sublessor after first deducting
                              Sublessee's reasonable costs, including but not
                              limited to brokerage fees, attorney's fees and
                              marketing costs.


Sublessor: Western Technology             Sublessee: Catapult
                                                     Communications

By: /s/ NORM WILLIAMS                     By: /s/ DAVID W. MAYFIELD
Title: President                          Title: President & COO
By:                                       By:
   ----------------------------              ------------------------------
Title:                                    Title:
   ----------------------------              ------------------------------
Date: 9/30/02                             Date: 9/30/02