<PAGE>


                                                                    Exhibit 10.5

                               LICENSE AGREEMENT

         This License Agreement ("Agreement"), is entered into as of May 13,
2002 ("Effective Date") between Oasys Telecom, Inc., a California corporation
with offices at 7060 Koll Center Parkway, Suite 340, Pleasanton, CA 94566
("Oasys"), and Larscom Incorporated, a Delaware corporation with offices at 1845
McCandless Drive, Milpitas, CA 95035 ("Larscom").

         WHEREAS:

         A. Oasys and Larscom are parties to the OEM Agreement (as defined
below) pursuant to which Oasys is obligated to manufacture for and supply to
Larscom the Products (also defined below);

         B. Larscom has expressed to Oasys its concerns regarding the continued
performance by Oasys of the OEM Agreement and requested Oasys to provide
assurances as to Oasys' continued performance. Among other reasons and to
address these concerns, Oasys has requested that Larscom agree to a
restructuring of the manufacture and supply arrangements between Oasys and
Larscom;

         C. Larscom has agreed to terminate the OEM Agreement, subject to the
execution of this Agreement and the granting thereby to Larscom of a
non-executory license with respect to certain Oasys technology, so as to
mitigate the losses which Larscom may suffer through the loss of the benefit of
its investment in the Products and the essential benefit of the bargain
negotiated by Larscom with respect to the OEM Agreement, including through the
continued design, development, manufacture, sale, use, support, improvement,
modifications and other exploitation and commercialization of the Products;

         D. As further consideration for the entry of this Agreement, and among
other consideration provided to Oasys, Larscom has agreed, at the request of
Oasys, to enter into that certain Supply Agreement relating to the purchase of
certain Products from Oasys (as amended, restated or otherwise modified from
time to time, the "Supply Agreement");

         NOW, THEREFORE, in consideration of the foregoing premises and the
mutual covenants and agreements contained herein, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereby agree as follows:

1.       DEFINITIONS

         1.1 "Customer Documentation" shall mean any user manuals, QuickStart
Guides, release notes and application notes relating to the Products.

         1.2 "Customer" shall mean a person or business enterprise which
acquires Larscom Equipment, from Larscom or from its distributors, resellers, or
others in Larscom's distribution channels, for its ordinary purposes or use in
its normal operations.

          1.3 "Larscom Equipment" shall mean the telecommunications equipment
manufactured, marketed and/or distributed by Larscom and may include the
Products.

         1.4 "Products" shall mean only the products listed on Exhibit A and all
related Customer Documentation.

         1.5 "OEM Agreement" shall mean the Non-Exclusive OEM Agreement executed
by Oasys and Larscom as of May 1, 2001, as amended by Amendment No. 1 to the
Non-Exclusive OEM Agreement entered into on September 7, 2001 (the "Amendment").

         1.6 "Proprietary Rights" shall mean all patent rights, copyrights, mask
work rights, trade secret rights, sui generis database rights, and all other
intellectual and industrial property rights of any kind anywhere in the
universe,

<PAGE>

together with all applications for any of the foregoing or any rights to renew,
extend or otherwise improve the foregoing.

         1.7 "Software" shall mean the software and firmware developed and owned
or licensed from third parties by Oasys and included in the Products or used in
the design, development, manufacture, testing, use or support of the Products,
and includes, without limitation, software used in or with FPGAs and any other
digital logic devices.

         1.8 "Testing Equipment" shall have the meaning set forth in Section 7.3
below.

         1.9 "Technical Information" shall include all mechanical drawings,
assembly drawings, silk screen art work, layouts, Gerber plots, bills of
materials, supplier lists, specifications, schematics, designs, processes,
protocols, know-how, tool and equipment descriptions, inspection, manufacturing,
test and quality control procedures specific to the Products, tooling designs
and fixture designs, Oasys history files related to Product defects and fixes
and other technical information pertinent to the design, development,
manufacture, testing and support of the Products and the development and use of
the Testing Equipment.

         1.10 "Technology Deliverables" shall include all documents, software,
information and materials which permit Larscom to exercise fully the rights
granted under this Agreement, including, without limitation, the Technical
Information, source code and object code for the Software developed and owned by
Oasys together with associated documentation and the Customer Documentation. A
list of the Technology Deliverables is attached to this Agreement as Exhibit B.

2.       LICENSE GRANT

         2.1 License Grant. Oasys hereby unconditionally grants to Larscom a
royalty-free, fully paid-up, non-exclusive, perpetual, irrevocable,
non-terminable (except as provided in Section 2.3 below), worldwide license,
under all of Oasys' Proprietary Rights in and to the Technical Information, the
Software, the Customer Documentation and the Technology Deliverables (the
"License"), to:

make, have made, use, sell, sell for use, offer for sale, import, distribute,
support and otherwise commercialize the Products and modifications thereof made
by or for Larscom;

copy, reproduce, distribute and support the Software (as object code only) and
Customer Documentation and modifications of the foregoing made by or for
Larscom, in connection with the commercialization of the Products;

debug, customize, update, enhance, make improvements to and otherwise modify the
Products, the Software, and the Customer Documentation; and

use, copy, reproduce, create derivative works of and modify the Technical
Information, the Technology Deliverables, the Software and the Customer
Documentation in connection with any of the foregoing.

         2.2 Sublicenses. The rights granted under the License may not be
sublicensed by Larscom except that, subject to the terms in Section 2.1, Larscom
may grant appropriate sublicenses: (a) to its Customers in connection with their
use of the Products, including the Software therein and Customer Documentation
therefor; (b) to third party resellers, distributors and others in Larscom's
channels of distribution; and (c) to Larscom's consultants, independent
contractors and third party manufacturers engaged by Larscom to provide
consulting design, manufacturing and testing services solely and exclusively in
connection with such party's provision of such services.

         2.3 Exceptions to Non-Terminability. The License shall terminate if
during the one (1) year period immediately following the Effective Date,
Larscom:

                  (a) files for or converts to a case for relief under Chapter 7
of the United States Bankruptcy Code("Bankruptcy Code") in which Larscom is the
debtor; or

                  (b) is dissolved.

<PAGE>

Nothing in this Section 2.3 shall affect or result in the termination of any
rights of Larscom hereunder which are transferred or licensed to any third party
except as an integral part of the liquidation action described in (a) and (b)
and, for the avoidance of doubt, nothing in this Section 2.3 shall affect any
transfer or license otherwise permitted by the terms of this Agreement. Further,
one (1) year after the Effective Date, this Section 2.3 shall cease to have any
further force or effect, and thereafter, the License shall be deemed to be
non-terminable.

         2.4 Larscom's Rights under Bankruptcy. Larscom's rights under this
Agreement are perpetual, irrevocable, and non-executory, notwithstanding any
other provision of this Agreement or any other contract, to the maximum extent
permitted by applicable law. In the event of the commencement of a bankruptcy
proceeding by or against Oasys under the Bankruptcy Code, the License grant to
Larscom in Section 2.1 shall continue in full force and effect. Under no
circumstances shall Larscom's exercise of the rights granted to it in Section
2.1 ever be construed as an infringement of Oasys' Proprietary Rights. In the
event that a bankruptcy court or other court of competent jurisdiction ever
determines by final judgment that this Agreement is executory, despite every
intention and effort by the parties to negotiate and document non-executory
rights for Larscom, and without implying any acceptance of the rejected concept
that it is legally impossible to create such a non-executory license for
Proprietary Rights, all rights and licenses granted under or pursuant to this
Agreement are, and shall otherwise be deemed to be, for purposes of Section
365(n) of the Bankruptcy Code, licenses of rights to "intellectual property" as
defined under Section 101 of the Bankruptcy Code; the Technical Information, the
Software, the Customer Documentation and the Technology Deliverables are
"embodiments" of such intellectual property; and the Supply Agreement is an
agreement "supplemental to" this Agreement. Furthermore, in such an event, the
parties agree that Larscom, as a licensee of such rights under this Agreement,
shall retain and may fully exercise all of its rights and elections under the
Bankruptcy Code and other applicable law, including any right by Larscom to
specific performance of this Agreement, since Oasys acknowledges and agrees that
the Technical Information, the Technology Deliverables, the Software and the
Customer Documentation are unique and that rejection of the License will cause
Larscom irreparable harm for which its legal remedies are inadequate; provided,
however, that nothing herein shall be deemed to constitute a present exercise of
such rights and elections.

         2.5 Enforcement and Maintenance of Proprietary Rights. If any
infringement or threatened infringement of Oasys' Proprietary Rights licensed
hereunder comes to the notice of Larscom, Larscom will notify Oasys of same.
Upon such notification, Oasys may, but shall not be obligated to, take such
steps as it considers appropriate, at its sole expense, provided that if Oasys
fails for any reason to take actions or commence proceedings to restrain the
infringement within thirty (30) days of notification by Larscom, Larscom will be
entitled to take such actions or commence such proceedings. Larscom will be
entitled in any such action or proceeding to take all necessary or desirable
steps in the name of Oasys and Oasys will cooperate and assist Larscom in taking
such steps. Without limiting the foregoing, if necessary or desirable to do so,
Larscom may file, prosecute and maintain such applications, registrations and
other filings and recordation in respect of Oasys' Proprietary Rights licensed
hereunder, in the name of Oasys.

3.       DELIVERY OF TECHNOLOGY DELIVERABLES.

         3.1 Deliverables. Immediately following execution of this Agreement
Oasys will deliver to Larscom a significant portion of the Technology
Deliverables and Oasys will complete its delivery of the Technology Deliverables
by not later than fifteen (15) business days after the Effective Date. The
Technology Deliverables, which the parties have listed in the attached Exhibit
B, will include, without limitation: (i) a copy of the Software developed and
owned by Oasys (as described in Exhibit B) in both source code and object code
formats; and (ii) a complete copy of the Technical Information in formats
compatible with Oasys' own design tools (for example, Microsoft Office, PCAD,
AutoCad, etc.) to the extent applicable. Oasys will not be required to reformat
or convert any of the Technology Deliverables into any particular format
requested by Larscom.

         3.2 Modification. To the extent necessary, the Technology Deliverables
delivered by Oasys to Larscom may be modified by Oasys, at Oasys' sole cost and
expense, to remove or alter occurrences of Oasys' trademarks, trade names,
product names and product numbers which are unique to and serve to identify
Oasys' products; provided however, that no such removal or alteration shall
affect the ability of Larscom to use the Technology Deliverables as contemplated
in the License and otherwise under this Agreement.

<PAGE>
4.       OWNERSHIP.

         Oasys acknowledges and agrees that Larscom shall own all right, title
and interest, including all Proprietary Rights, in and to any customizations,
updates, enhancements or improvements to, or derivative works or other
modifications of, the Technical Information, the Software, the Customer
Documentation and the Technology Deliverables, created, developed or made by or
for Larscom. Larscom acknowledges and agrees that, except for the License and
other rights granted hereunder or pursuant to that certain letter agreement
between the parties dated April 9, 2002, Oasys shall continue to own all right,
title and interest, including the underlying Proprietary Rights as they
currently exist, in and to the Technical Information, the Software, the Customer
Documentation and the Technology Deliverables and any and all modifications,
improvements and/or derivative works thereof or thereto made by or for Oasys.

5.       NON-EXECUTORY AGREEMENT.

         5.1 License Fees. Oasys acknowledges and agrees that there are no
license fees, royalties or other amounts payable by Larscom in respect of the
License or the rights granted pursuant to this Agreement.

         5.2 Full Performance. The parties acknowledge and agree that upon
Larscom entering into this Agreement and the Supply Agreement, Larscom will have
fully paid for all consideration payable with respect to the grant of the
License and performed all of its obligations under this Agreement, and Larscom
has no further performance obligations under this Agreement, or any other
agreement, that must be satisfied in order to have fully performed its
obligations under this Agreement. There are no other conditions to the
effectiveness of this Agreement. Specifically, none of Larscom's performance
obligations under the Supply Agreement are relevant to the interpretation of the
non-executory nature of this Agreement, since the intent of the parties is that
this Agreement function as a non-executory transfer of rights.

6.       INTENTIONALLY LEFT BLANK.

7.       REPRESENTATIONS AND WARRANTIES; DISCLAIMER.

         7.1 General Representations and Warranties. Each party hereby
represents and warrants to the other party as follows:

                  (a) Corporate Existence, Power and Authorization. Such party:
(i) is a corporation duly organized, validly existing and in good standing under
the laws of the state in which it is incorporated; (ii) has the corporate power
and authority and the legal right to enter into this Agreement and to perform
its obligations hereunder; and (iii) has taken all necessary corporate action on
its part to authorize the execution and delivery of this Agreement and the
performance of its obligations hereunder.

                  (b) Enforcement of Obligations. This Agreement has been duly
executed and delivered on behalf of such party, and constitutes a legal, valid
and binding obligation, enforceable against such party in accordance with its
terms.

                  (c ) No Consents. All necessary consents, approvals and
authorizations of all governmental authorities and other persons required to be
obtained by such party in connection with this Agreement have been obtained.

                  (d) No Conflict. The execution and delivery of this Agreement
and the performance of such party's obligations hereunder: (i) do not conflict
with or violate any requirement of applicable laws or regulations and (ii) do
not conflict with, or constitute a default under, any contractual obligation of
it.

                  (e) Not in Bankruptcy. Neither party has made, nor has any
current intention of making, an assignment to or for the benefit of its
creditors, nor is aware of any petition or proceeding in bankruptcy having been
filed or threatened against it, nor does it have intention of filing any such
petition.

<PAGE>

         7.2 Intellectual Property. Oasys represents and warrants to Larscom
that: (i) except as listed on Exhibit B, Oasys is the sole and exclusive owner
of all right, title and interest, including all Proprietary Rights, in and to
the Technical Information, the Software, the Customer Documentation and the
Technology Deliverables; (ii) Oasys has not granted to any third party any
license or other interest in the Technical Information, the Software, the
Customer Documentation or the Technology Deliverables which would prevent,
impair or impede Larscom's exercise of the License or other rights granted to
Larscom under this Agreement; (iii) no Proprietary Right of any third party
would be infringed by Larscom's exercise of the License and the other rights
granted to Larscom under this Agreement; (iv) Oasys has not misappropriated or
infringed the Proprietary Rights of any third party in granting to Larscom the
License or other rights under this Agreement; provided that Larscom's sole and
exclusive remedy on a breach of this representation is set forth in Section 7.5
below; (v) Oasys is not aware of any infringement or misappropriation by a third
party of the Technical Information, the Software, the Customer Documentation or
the Technology Deliverables; and (vi) all Proprietary Rights in the Technical
Information, the Software, the Customer Documentation and the Technology
Deliverables are subsisting and have not been adjudged invalid or unenforceable,
in whole or in part; and (vii) the Technical Information, the Software, the
Customer Documentation and the Technology Deliverables are free and clear of any
liens, encumbrances or security interests.

         7.3 Technology Deliverables. Oasys further represents and warrants to
Larscom that: (a) the Technology Deliverables as delivered to Larscom hereunder
contain all technology, software, know-how and other information to enable a
person of ordinary skill in the art to manufacture each of the Products; and (b)
each unit of Product when so manufactured (and in the absence of any defect in
materials or workmanship) would: (i) subject to the following subsection (ii),
conform materially to its specifications as set forth in Exhibit C; (ii) comply
with the following governmental and industry certification requirements as
applicable to each Product: UL/cUL, NEBS-3 (once such Product has been
certified), FCC and CE mark (once such Product has been certified)
certifications; and (iii) materially comply with all other applicable federal,
state and local laws and regulations. Notwithstanding the foregoing, Oasys makes
no warranty (express, implied or statutory) with respect to a Product, nor will
Oasys be held liable to Larscom for breach of warranty for any claim made
against such Product, to the extent that such claim arises out of (i) a defect
in Larscom's manufacture of that Product, including any defect in materials or
workmanship, (ii) any modification to Oasys' specifications therefor by or on
behalf of Larscom, or (iii) the use of such Product in a manner contrary to the
published documentation for that Product. Notwithstanding the foregoing, the
Product identified as Orion 5001 Shelf & Backplane (part no. 815-00074-002) will
comply with the UL/cUL and NEBS-3 certification requirements once the
certification process for such Product has been completed.

         7.4 Testing Equipment. Oasys further represents and warrants to Larscom
that the Technology Deliverables contain all technology, software, know-how and
other information required for Larscom to precisely duplicate Oasys' testing
equipment for the Products (the "Testing Equipment") and testing specifications
and protocols. Subject to the foregoing, Oasys shall not be required to transfer
any of its own Testing Equipment to Larscom under this Agreement.

         7.5 Indemnity. Oasys shall defend, indemnify and hold Larscom, its
affiliates and Customers, and each of their respective directors, officers,
employees, agents and representatives harmless from any and all claims, actions,
damages or other liabilities, including reasonable attorney's fees, arising from
any breach of any representation or warranty of Oasys in this Agreement,
including any claim that any Product, any portion thereof or any related
Proprietary Rights therein or the exercise of such rights, constitutes an
infringement or unauthorized use of any third party Proprietary Rights (each, an
"Infringement Action"). Larscom shall at all times have the right to instruct
its own counsel and defend and settle any Infringement Action where Oasys fails
to take reasonable and timely steps to defend such action. Notwithstanding the
foregoing, Oasys shall have no obligation to indemnify Larscom against any
Infringement Action arising out of (i) the Larscom Equipment, (ii) the
combination of the Larscom Equipment and any Product or (iii) any modification
of the Products by Larscom, its affiliates or Customers.

8.       MISCELLANEOUS.

         8.1 Entire Agreement. This Agreement (and all Exhibits hereto)
supersede all other prior negotiations, representations, understandings and
agreements between or among the parties relating to the subject matter of this

<PAGE>

Agreement, except for that certain letter agreement between the parties dated
April 9, 2002 which shall continue in full effect in accordance with its terms.

         8.2 Amendment. No agreements amending, modifying or supplementing the
terms hereof shall be effective except by means of a written document signed by
the duly authorized representatives of both parties.

         8.3 Successors and Assigns. This Agreement shall be binding upon and
inure to the benefit of Oasys, Larscom and their respective successors and
permitted assigns. Larscom will not enter into any transaction for the purpose
of selling its license rights hereunder to any third party without any other
legitimate business purpose. Notwithstanding the foregoing, either party may at
any time assign or otherwise transfer to any other person or entity all or part
of its rights or obligations under this Agreement in connection with an
acquisition of all or substantially all of its assets or business relating to
the Products or this Agreement or an acquisition of a controlling interest in
its equity securities or in connection with a merger, consolidation,
reorganization or other like transaction. Except as provided herein, neither
party may assign or transfer any of its rights or obligations under this
Agreement without the prior written consent of the other party, which consent
shall not be unreasonably withheld (and any purported assignment without such
consent shall be void).

         8.4 Notices. All notices, consents or approvals required by this
Agreement shall be in writing and shall be deemed given five (5) days after
being sent by certified or registered mail, postage prepaid, or when received
after being sent by facsimile (confirmed by such certified or registered mail)
or by commercial overnight courier service with tracking capabilities, to the
parties at the addresses provided below or such other addresses as may be
designated in writing by the respective parties pursuant to the terms of this
notice provision:

          Initial Addresses for Notice:
          Oasys Telecom, Inc.                      Larscom Incorporated
          7060 Koll Center Parkway, Suite 340      1845 McCandless Drive
          Pleasanton, CA 94566                     Milpitas, CA 95035
          Attn: Mr. Gerard Miille, CEO             Attn: Chief Executive Officer

         8.5 Governing Law and Legal Actions. This Agreement shall be governed
by and construed in accordance with California law as applied to transactions
taking place in California between California residents. All disputes between
the parties arising out of or relating to this Agreement (other than actions
seeking only equitable remedies) shall be settled by binding arbitration
pursuant to the Commercial Arbitration Rules of the American Arbitration
Association by an arbitrator who is knowledgeable about telecommunications
equipment. The arbitrator may award any legal or equitable remedy and may, in
his discretion, require one party to pay the costs of the arbitration as well as
the fees and expenses, including reasonable attorneys' fees, of the other party.
In the absence of any such ruling, each party shall bear its own costs in
connection with an arbitration proceeding hereunder and the parties shall share
the costs of the arbitration equally.

         8.6 Waiver. The failure of Oasys or Larscom to enforce a right or
remedy under this Agreement shall not act as a waiver of that right or remedy or
the ability to assert that right or remedy relative to the particular situation
involved. The waiver by either party of a breach of any provisions contained in
this Agreement shall be effective only if set forth in a writing signed by both
parties and shall in no way be construed as a waiver of any succeeding breach of
such provision or the waiver of the provision itself.

         8.7 Headings. Headings included herein are for convenience only and
shall not be used to interpret or construe this Agreement.

         8.8 Severability. If any provision of this Agreement shall be held
void, invalid, illegal or unenforceable, that provision shall be limited or
eliminated to the minimum extent necessary so that this Agreement shall
otherwise remain in full force and effect and fully enforceable.

         8.9 Construction of Agreement. This Agreement is the product of
extensive negotiations between the parties hereto and no party shall be deemed
the drafter of this Agreement. No portion of this Agreement shall be construed
against any party as drafter.

<PAGE>

         8.10 No Joint Venture. Nothing contained in this Agreement shall be
deemed or construed as creating a joint venture or partnership between the
parties. Except as expressly set forth, no party is by virtue of this Agreement
authorized as an agent, employee or legal representative of any other party, and
the relationship of the parties is, and at all times shall continue to be, that
of independent contractors.

         8.11 Counterparts. This Agreement may be executed in counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

<PAGE>

         IN WITNESS WHEREOF, the parties have executed this Agreement to be
effective as of the Effective Date.

Larscom Incorporated                         Oasys Telecom, Inc.

By:/s/ Daniel L. Scharre                     By: /s/ Gerard Miille
   ----------------------                        -------------------

Name: Daniel L. Scharre                      Name: Gerard Miille
     ------------------                            --------------

Title: President and Chief                   Title: President and Chief
         Executive Officer                            Executive Officer
         -----------------                            -----------------

<PAGE>

                                    EXHIBIT A

                                    PRODUCTS
 ---------------- --------------------------------------------------------------
 Part Number      Item
 ---------------- --------------------------------------------------------------
 815-00063-001    Orion 5000 23" Shelf & Backplane
 ---------------- --------------------------------------------------------------
 815-00073-002    Orion 5000 19" Shelf & Backplane
 ---------------- --------------------------------------------------------------
 810-00062-010    MPU Module with Ethernet Aux Board, -48V
 ---------------- --------------------------------------------------------------
 810-00068-012    Programmable M13 Module, T1, -48V, "+" Version
 ---------------- --------------------------------------------------------------
 810-00068-003    Programmable M13 Module, E1, -48V
 ---------------- --------------------------------------------------------------
 810-00068-009    T3-Only M13 Module, -48V
 ---------------- --------------------------------------------------------------
 810-00067-002    OMX-3 Module, -48V
 ---------------- --------------------------------------------------------------
 810-00066-001    M13 IN Rim
 ---------------- --------------------------------------------------------------
 810-00065-001    M13 OUT Rim
 ---------------- --------------------------------------------------------------
 810-00069-002    OMX3 IN Rim
 ---------------- --------------------------------------------------------------
 810-00069-001    OMX3 OUT Rim
 ---------------- --------------------------------------------------------------
 815-00050-009    Module Blank
 ---------------- --------------------------------------------------------------
 835-00081-002    RIM Blank
 ---------------- --------------------------------------------------------------

 ---------------- --------------------------------------------------------------
 815-00077-002    Orion 5003 Shelf & Backplane, 1 MPU w/Aux, 2 OMX-3's
 ---------------- --------------------------------------------------------------
 815-00074-002    Orion 5001 Shelf & Backplane, 1 MPU w/Aux, 2 T3-Only M13's
 ---------------- --------------------------------------------------------------
 810-00062-009    MPU Module with Ethernet Aux Board, -48 V, no faceplate
 ---------------- --------------------------------------------------------------
 810-00067-003    OMX-3 Module, -48V, no faceplate
 ---------------- --------------------------------------------------------------
 810-00068-006    T3-Only M13 Module, T1, -48V, no faceplate
 ---------------- --------------------------------------------------------------

 ---------------- --------------------------------------------------------------
 815-00011-xxx    Cable, UID, Various lengths
 ---------------- --------------------------------------------------------------
 815-00055-xxx    Cable, Null Modem, Various lengths
 ---------------- --------------------------------------------------------------
 815-00064-xxx    Cable, RIM to Champ Plug, Various lengths
 ---------------- --------------------------------------------------------------
 815-00065-xxx    Cable, Champ Receptacle to Champ Receptacle, Various Lengths
 ---------------- --------------------------------------------------------------
 815-00066-xxx    Cable, Champ Receptacle to Wirewrap, Various Lengths
 ---------------- --------------------------------------------------------------
 815-00069-xxx    Cable, Champ Receptacle to Champ Plug, Various Lengths
 ---------------- --------------------------------------------------------------
 815-00082-001    Cable, OMX3 Rim to M13 Rim, 14"
 ---------------- --------------------------------------------------------------
 815-00082-002    Cable, OMX3 Rim to M13 Rim, 24"
 ---------------- --------------------------------------------------------------
 815-00033-xxx    Cable, DS3 Coax, Straight BNC's, Various Lengths
 ---------------- --------------------------------------------------------------
 815-00053-xxx    Cable, DS3 Coax, Straight/Right Angle BNC's, Various Lengths
 ---------------- --------------------------------------------------------------
 131-00004-001    Adapter, Right Angle, BNC, Male-to-Female
 ---------------- --------------------------------------------------------------

 ---------------- --------------------------------------------------------------
 890-00009-002    Version 4.1 Basic Software including terminal, telnet, SNMP,
                    & Web Server
 ---------------- --------------------------------------------------------------
 ---              Operations Manuals, Various
 ---------------- --------------------------------------------------------------

 ---------------- --------------------------------------------------------------

<PAGE>

                                    EXHIBIT B

                             TECHNOLOGY DELIVERABLES

                            I. Technical Information

1.   All Product Documentation included in the Escrow on January 23, 2002.

2.   All updates and current documentation as available on the date of this
     Agreement for the items in Escrow that were updated since the January 23,
     2002 date.

3.   Complete Documentation created by Oasys for each of the products listed in
     Exhibit A that are not included in escrow

         a. 815-00074-002 - Orion 5001, Shelf and Backplane, 1MPU w/Aux, 2 T3
            only M13's
         b. 810-00068-006 - T3-only M13 Module, T1, -48V, no faceplate
         c. 815-00033-xxx - Cable, DS3 Coax, Straight BNC's, Various Lengths
         d. 815-00053-xxx - Cable, DS3 Coax, Straight/Right Angle BNC's, Various
            Lengths
         e. 131-00004-001 - Adapter, Right Angle, BNC, Male to Female

4.   To the extent not included in items 1 through 3 above, all mechanical
     drawings, assembly drawings, silk screen art work, layouts, Gerber plots,
     bills of materials with AVL, specifications, schematics, designs,
     processes, protocols, know-how, tool and equipment descriptions,
     inspection, manufacturing test and quality control procedures specific to
     the Products, tooling designs and fixture designs, Oasys history files
     related to Product defects and fixes and other technical information
     pertinent to the design, development, manufacture, testing and support of
     the products listed in Exhibit A.

5.   All product development documentation associated with the requirements,
     design, and qualification of the products listed in Exhibit A. This would
     include but not be limited to such items as Functional Specifications,
     Design Specifications, relevant engineering design notes, Qualification
     Test Plans, and Qualification Test Results. Oasys will have no obligation
     to provide Product Requirements Documents hereunder.

6.   An itemized list of the CAD tools and versions used in the design and
     development of the products in Exhibit A. The would include Schematic
     Capture, PCB layout, Mechanical Design, and other tools utilized in the
     creation, viewing, and modifying documentation for the design, development
     and fabrication of the products in Exhibit A.

7.   All test plans, procedures, reports, and other documentation required to
     replicate Oasys' engineering validation test, manufacturing test, and
     repair functions. All equipment lists, descriptions, designs, drawings
     associated with replicating test and manufacturing equipment and fixtures.

<PAGE>

II.  Software

1.   Source code and all of the files associated with the software and FPGA for
     Release 4.1. This includes SNMP MIBs (private and public) associated with
     the current release.

2.   All object files that are required to operate the products in Exhibit A.
     This includes the file images for the boot proms, flash devices, FPGA, PLD,
     and other devices requiring programmed images.

3.   All software used by Oasys or its consultants, suppliers, vendors, contract
     manufacturers or other third party contractors for designing, developing,
     manufacturing, verification and testing the products in Exhibit A. For
     software packages purchased, a list by vendor and version of the software
     used and licensed for the purpose of developing, manufacturing,
     verification and testing will be supplied. For software developed by Oasys
     for the purpose of assisting with the design, developing, manufacturing,
     verification and testing, all the source code and object files will be
     supplied as part of this Agreement.

The software listed below has been licensed to Oasys by third parties. Larscom
acknowledges and agrees that it must obtain its own licenses to the following
Software:

4.   Third party Software used and licensed for the design and development of
     Product:

          o    Xilinx 4.1i Foundation Development System. Used for FPGA design.
          o    Viewlogic Viewdraw with Xilinx translators. Used for FPGA
               schematic capture.
          o    EST (Now Windriver) CLKVPA-C32-XM Vision CLICK Source debugger
               with probe for 683xx. Used for loading Boot Code into the MPU
               Module.
          o    AutoCad Lite V97 or later. Used for mechanical design.
          o    PCAD 2001 with integrated autorouter by Altium. Used for PC Board
               design of all modules except MPU Module.
          o    PCAD V8.5. Used for PC Board design of MPU Module.
          o    Spectra Router Ver. 10. Used for autorouting of complex PC
               Boards.
          o    Camtastic 2000. Gerber viewer for PC Boards.
          o    Greenhills Software, Inc. "Multi" Environment cross C/C++
               Compiler, Assembler, Linker for 68K target with ThreadX RTOS
               support. Need this environment to use our Make Files

5.   Third Party Software that is integrated into the Product:

          o    Express Logic ThreadX RTOS for 68K processors. Version G3.0F.3.0F
               for 68360. Real Time Operating System for MPU Module.
          o    Treck, Inc. (Now Elmic Systems) Ver. 2.2 Base TCP-IP Source
               Code(#TUTCPSRC), Telnet Source Code (#TUTELSRC), and Emanate/Lite
               SNMP Agent Source Code (#TUAGNSRC). Networking software
               integrated into MPU code.

<PAGE>

III. Customer Documentation

Customer Documentation for version 4.1 of the Products includes:

1.   Operations Manual for Exchange Mux II (Orion 5000) supporting release 4.1

2.   Quick Start Guide for Exchange Mux II (Orion 5000) supporting release 4.1

3.   Operations Manual for Mini Mux 155 (Orion 5003) supporting release 4.1

4.   Quick Start Guide for Mini Mux 155 (Orion 5003) supporting release 4.1

5.   Operations Manual for Mini Mux 280 (Orion 5001) supporting release 4.1

6.   Quick Start Guide for Mini Mux 280 (Orion 5001) supporting release 4.1

<PAGE>

                                    EXHIBIT C

                                 Specifications

Please see attached Oasys product specification sheets for:

1.   Mini-Mux 155 (OC-3/STM-1)

2.   Mini-Mux 280 M13 Multiplexer

3.   Exchange Mux II Advanced Multiplexer


                        [To be attached prior to signing]