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                                                                 Exhibit 10.1

This Marketing and Distribution Agreement is made, entered into, and effective
as of March 21, 1997

                      between:
                               SHIVA CORPORATION, a Massachusetts
                               corporation, whose registered office is at
                               28 Crosby Drive Bedford, MA, USA
                               (hereinafter called "SHIVA")

                      and:
                               NORTHERN TELECOM LIMITED, a Canadian 
                               corporation, having executive offices at
                               8200 Dixie Road, Brampton, Ontario, Canada
                               L6T 5P6 on behalf of itself and its
                               SUBSIDIARIES and AFFILIATES
                               (hereinafter collectively called "NORTEL")

WHEREAS, NORTEL and SHIVA have established a relationship where NORTEL
purchases Remote LAN Access products from SHIVA; and

WHEREAS, the PARTIES desire to change the relationship to permit NORTEL to
acquire manufacturing rights from SHIVA for certain of the products and the
ability to distribute such products pursuant *************************
bearing licenses, as the case may be; and

WHEREAS, the PARTIES wish to explore new opportunities in the CARRIER/ISP
MARKET, as defined below:;

NOW, THEREFORE, IN CONSIDERATION OF THE MUTUAL PROMISES HEREINAFTER SET FORTH,
THE PARTIES AGREE AS FOLLOWS:

1.0   DEFINITIONS

      Terms in the MARKETING AGREEMENT (other than names of PARTIES and
Section headings) which are in capital letters shall have the meanings set
forth in this Article 1 for all purposes in connection with the MARKETING
AGREEMENT.

1.1   AFFILIATE is defined as any:

     (i)   manufacturing licensee, which is a THIRD PARTY with which NORTEL
or its SUBSIDIARIES has entered into an agreement, now or in the future,
permitting such THIRD PARTY to manufacture products substantially based upon
or equivalent to products designed by or for NORTEL;

<PAGE>  1

     (ii)  joint venture, partnership, corporation, or similar association
between NORTEL or SHIVA, as the case may be, or their respective SUBSIDIARIES
and one (1) or more THIRD PARTIES, in which NORTEL or SHIVA, as the case may
be, or their respective SUBSIDIARIES owns or controls, directly or
indirectly, a percentage of shares or other mechanism of control that allows
NORTEL or SHIVA as the case may be, or their respective SUBSIDIARIES, to
effectively control the joint venture, partnership or similar association.;
and/or 

    (iii)  corporation or other legal entity effectively controlled, directly
or indirectly, by NORTEL or SHIVA, as the case may be, through the ownership
or control of shares or other securities in such corporation or legal entity.

1.2   AVERAGE SALES PRICE shall mean the calculated average price for SPECIFIC
PRODUCT sold and invoiced to the CUSTOMER for a specified period.

1.3   BACKGROUND INTELLECTUAL PROPERTY shall mean INTELLECTUAL PROPERTY of a
PARTY that is conceived, created, developed or reduced to practice prior to,
or independently of, the activities under the MARKETING AGREEMENT or the
MA.

1.4   CARRIER/ISP's and CARRIER/ISP MARKET are defined as Local Exchange 
Carriers, Inter-exchange Carriers, Post-Telephone and Telegraphs (PTT's),
Competitive Access Carriers and Telco's, Internet Service Providers (ISPs) and
On-Line Service Providers.

1.5   CONFIDENTIAL INFORMATION shall have the meaning set forth in Article 13.

1.6   CUSTOMER means any entity which purchases products, directly or
indirectly, from NORTEL.

1.7   DOCUMENTATION means the customer documentation, such as user guides, and
design documentation reasonably required by NORTEL to provide first level
support to its CUSTOMERS.

1.8   EFFECTIVE DATE means the date the MARKETING AGREEMENT is entered into as
written at the beginning of the MARKETING AGREEMENT.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

1.9   ENTERPRISE and ENTERPRISES means any organization(s) that is not a
CARRIER/ISP.

1.10  ENTERPRISE NETWORKS shall mean the NORTEL line of business of that name
that is responsible for development and sale of NORTEL products to
ENTERPRISES.

1.11  ***************shall mean the *********** for the ******** and any
relevant documentation required to ************* and ******* the ********
contained in *************** and to **************************************
************** or built in accordance with ****************************. This
shall include, but is not limited to, ***************************************
**********************************.

1.12  FCS shall mean the date of the first customer shipment by either PARTY
of a SPECIFIC PRODUCT or FEATURE, including hardware, SOFTWARE and
DOCUMENTATION, other than for trial purposes.  In the case of SHIVA's FCS to
NORTEL, such FCS shall be subject to prior acceptance by NORTEL.

1.13  FEATURE or FEATURES shall mean the implementation in hardware, firmware
and/or software of a discrete set of features or functionality as described
in a SPECIFIC PRODUCT/FEATURE ADDENDUM, and shall include any future FEATURES
added to the MARKETING AGREEMENT by addition to Exhibit E of a SPECIFIC
PRODUCT/FEATURE ADDENDUM.

1.14  FOREGROUND INTELLECTUAL PROPERTY shall mean INTELLECTUAL PROPERTY first
conceived, created, developed or reduced to practice by, or on behalf of a
PARTY in the course of performing activities pursuant to the MARKETING
AGREEMENT or the MTDA.

1.15  INTELLECTUAL PROPERTY shall mean any invention, patent, trade mark,
utility model, copyright, industrial design, mask work or integrated circuit
topography right, or any right of whatsoever nature in processes, techniques,
improvements, modifications, computer software and data, CONFIDENTIAL
INFORMATION, trade secrets or know-how, or any intangible right or privilege
of a nature similar to any of the foregoing, in every case in any part of the
world and whether or not registered, and shall include all granted
registrations in respect of any such right.

1.16  ****************************** shall mean the CARRIER/ISP's in all
markets other than ************** including but not limited to **************
************************************.

1.17  INTERNET THRUWAY APPLICATION shall mean NORTEL's marketing solution
comprised of NORTEL's (i) Access Node product or equivalent product, (ii)
Rapport product and (iii) Magellan product, to provide end-to-end congestion
relief for local telephone companies.


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1.18  MINIMUM MARKET PERFORMANCE OBJECTIVE means NORTEL's achievement of
PRODUCT revenues in ************* as described in Exhibit G, which shall be
updated as required, by the PARTIES.

1.19  MANUFACTURING KNOW-HOW PACKAGE means the technical information, in
digital format where practical, including the hardware design, design
drawings, schematics, instructions for manufacturing, testing or assembling
products, parts and vendors lists, object code, manufacturing training
materials, and any other manufacturing know-how information which is
reasonably required to enable NORTEL to manufacture certain PRODUCTS.

1.20  MARKETING AGREEMENT is defined as this Marketing and Distribution
Agreement, as amended, modified, supplemented or otherwise altered from time
to time.

1.21  MASTER TECHNOLOGY DEVELOPMENT AGREEMENT or MTDA shall mean the agree-
ment executed by the PARTIES on or about March 31, 1997, containing the terms
governing research and development and the funding thereof.

1.22  NET SALES PRICE shall mean the price computed in accordance with Exhibit
H.

1.23  ****************************************** means the named accounts
defined in Exhibit A which comprise the market for which SHIVA grants NORTEL
*********************************, according to the terms described in
Article 5 and Exhibit E of the MARKETING AGREEMENT.

1.24  PARTY shall mean NORTEL or SHIVA.

1.25  PARTIES shall mean NORTEL and SHIVA.

1.26  PRODUCT or PRODUCTS shall mean the products described in Exhibit E, and
such future products as are added to the MARKETING AGREEMENT by addition of a
SPECIFIC PRODUCT/FEATURE ADDENDUM to Exhibit E, in each case the PRODUCT is
inclusive of hardware, SOFTWARE, firmware and documentation, as is
applicable.

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1.27  RIGHT TO MANUFACTURE FEE or RTM FEE shall mean the payment that covers
all manufacturing rights for hardware, firmware, SOFTWARE and documentation
associated with a SPECIFIC PRODUCT including transfer of the MANUFACTURING
KNOW-HOW PACKAGE and assistance for manufacturing start up, as detailed in
Article 5 of the MARKETING AGREEMENT.

1.28  SERVICE PROVIDER GROUP or SPG shall mean a group of employees provided
by SHIVA ********* to support NORTEL global sales, marketing and support as
further described in Article 12 and Exhibit I.

1.29  SHIVA LIST PRICE shall mean SHIVA's then current U.S. customer list
price.

1.30  SHIVA R&D DELIVERABLE DEPENDENCIES shall mean the FEATURES as set forth
in Exhibit F, and such future FEATURES to be delivered by SHIVA as are agreed
upon pursuant to the terms of the MTDA.

1.31  SOFTWARE shall mean software in object code form which shall be used in
each PRODUCT.

1.32  SPECIFIC PRODUCT shall mean a specific PRODUCT as designated in a SPECIFIC
PRODUCT/FEATURE ADDENDUM in Exhibit E or in a SPECIFIC PRODUCT/FEATURE ADDENDUM
added by amendment to Exhibit E.

1.33  SPECIFIC PRODUCT/FEATURE ADDENDUM shall mean an addendum to Exhibit E
of the MARKETING AGREEMENT which describes the ownership, licensing, marketing
and distribution rights pertaining to a SPECIFIC PRODUCT.

1.34  SPECIFICATION shall mean the functional specifications for a SPECIFIC
PRODUCT agreed by the PARTIES and any future functional specifications that
are agreed by the PARTIES in the corresponding section of Exhibit E or the
MASTER TECHNOLOGY DEVELOPMENT AGREEMENT.

1.35  SUBSIDIARY shall mean any corporation or other legal entity in which
Northern Telecom Limited or SHIVA, as the case may be, directly or indirectly
owns and controls, and continues to own and control, fifty percent (50%) or
more of the shares or other ownership interest entitled to elect the board of
directors or its equivalent.

1.36  THIRD PARTY or THIRD PARTIES shall mean an individual(s) or entity(ies)
other than NORTEL or SHIVA.

2.0   RESEARCH AND DEVELOPMENT ("R&D")

2.1   Development and Funding Process. SHIVA shall review its development
plans, including all patents and patent applications related to the PRODUCTS,
with NORTEL on an ongoing basis.  The PARTIES shall agree, in writing, upon
those features that add demonstrable value within the CARRIER/ISP MARKET
which one or both of the PARTIES shall undertake to develop.  The terms and
conditions of R&D activities and ownership of INTELLECTUAL PROPERTY shall be
described in the MTDA.  In addition, the PARTIES shall add the newly developed
PRODUCT(S) or FEATURE(S), as applicable, to the MARKETING AGREEMENT including

<PAGE>  5

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terms describing any royalty, RTM Fees or marketing terms that may apply to
such PRODUCT(S) or FEATURE(S).

2.2   NORTEL agrees to **** the R&D program through quarterly payments in 1997
of ********************************************************** for a total of
********************************************************* in 1997. Subject to
mutual agreement by the PARTIES and pursuant to a project addendum of the
MTDA, the disbursement of the funds toward the development of PRODUCT(S) or
FEATURE(S) shall be based on specific feature content which adds demonstrable
value within the CARRIER/ISP MARKET.  NORTEL's quarterly payments of ***
****************************************************** shall, subject to the
terms and conditions of the MTDA, be paid ************************ of
NORTEL's receipt of invoice from SHIVA.  Such invoice from SHIVA shall be
delivered to NORTEL no earlier than the fifteenth day of the third month of
each quarter that the quarterly payments are required to be made.  SHIVA
agrees to fund no less than *****************************************
**************** in 1997 in R&D related to ****************** and CARRIER/ISP
related features which shall also be available to ENTERPRISES.  As additional
consideration for R&D funding by NORTEL, NORTEL shall receive the following: 
(a) rights to prioritize various future FEATURES and enhancements of the
PRODUCT platforms and CARRIER/ISP MARKET FEATURE(S), as required by NORTEL,
(b) a list of committed PRODUCT(S) and/or FEATURE(S) for the ****************
***************************************** invested by SHIVA set forth in a
project addendum to the MTDA and (c) NORTEL SPECIFIC FEATURES identified as
license type E, as the case may be.

2.3   SHIVA's failure to complete work on a project set forth in a project
addendum of the MTDA, to the extent that such failure is not cured within the
terms described in the MTDA thereby constituting a breach of the MTDA and
such breach occurs **************, shall have the following effect in
relation to this MARKETING AGREEMENT:

      A.  The ****************** provisions described in Exhibit E, Addendum
3, under Rapport 112, ********************, shall be ********* at NORTEL's
option.

      B.  At NORTEL's option, NORTEL may *************************, pursuant
to the provisions of Article 14, for purposes of development and support but
may not create derivative works from the ******************.  Consistent with
the provisions of Article 14, NORTEL may continue to support existing
CUSTOMERS on a ************ basis and may manufacture and pay a royalty to
SHIVA *******************************************.

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      C.  At NORTEL's option, NORTEL may acquire ***************************
*******, including the *******************************************************
********************** by payment of the amounts described in Article 16.5.

3.0   REGULATORY COMPLIANCE

3.1   SHIVA shall be responsible for obtaining any required regulatory
approvals for the PRODUCTS designed by SHIVA even if such PRODUCT is
manufactured by or supplied to NORTEL by a party other than SHIVA. NORTEL
shall be responsible for obtaining any regulatory approvals for the PRODUCTS
that it designs or PRODUCTS of SHIVA design in the event of NORTEL changes to
such SHIVA design.  In addition, to the extent that any regulatory approval
needs to be acquired solely due to the change in manufacturer from SHIVA to
NORTEL, NORTEL agrees to fund such additional approval.  On an ongoing basis,
SHIVA agrees to provide NORTEL with a bill of materials including all UL
approval numbers to assist in obtaining any additional regulatory approvals
for the PRODUCTS in achieving compliance with regulations.  For PRODUCTS that
SHIVA designs, in the event that SHIVA has not obtained such approvals in a
country in which NORTEL desires to sell the PRODUCTS, SHIVA shall use
reasonable efforts to obtain such approvals following a written request by
NORTEL.  The PARTIES shall provide each other with cooperation and assistance
to obtain such approvals and any joint approvals, where applicable. In the
event that SHIVA does not make any direct or indirect sales (excluding sales
through NORTEL) of the PRODUCTS into such country within ******************
of SHIVA's obtaining such approval, NORTEL shall reimburse SHIVA for the
reasonable costs to SHIVA of obtaining such approval.

4.0   OWNERSHIP AND LICENSES

4.1   Technology Ownership.    Unless otherwise specifically agreed, each
PARTY shall retain ownership of its BACKGROUND INTELLECTUAL PROPERTY.  The
PARTIES shall agree, in writing, on the level of funding and ownership of
FOREGROUND INTELLECTUAL PROPERTY developed under the MTDA.

4.2   Licensing Terms.  The PARTIES shall agree to the marketing, distribution
and licensing rights for PRODUCTS (including terms governing BACKGROUND
INTELLECTUAL PROPERTY and FOREGROUND INTELLECTUAL PROPERTY embodied in such
PRODUCTS).  The marketing, distribution and licensing rights for existing
PRODUCTS and FEATURES are set out in the SPECIFIC PRODUCT/FEATURE ADDENDA in
Exhibit E.  The marketing, distribution and licensing rights for future
PRODUCTS and FEATURES, as agreed by the PARTIES, shall be added by addition
of SPECIFIC PRODUCT/FEATURE ADDENDA to Exhibit E.  If appropriate, future
PRODUCTS or FEATURES shall be designated as being subject to Type A, Type B,
Type C, Type D, Type E or Type F licenses.  In the event that the chosen

<PAGE>  7

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license type is a *********************** or ********************, the
royalty payment and ***************** shall be set out in the corresponding
SPECIFIC PRODUCT/FEATURE ADDENDUM.  The current license categories shall not
preclude the PARTIES from augmenting the terms of an existing license type,
or from creating new license types.  Any such augmented or additional license
type must be agreed to, in writing, by the PARTIES.

4.3   ************************************************* for ****** Purchase of
***************************************************************

      4.3.1  SHIVA grants to NORTEL a *************************************
license  under SHIVA's INTELLECTUAL PROPERTY to use, sublicense for use (and
in the  case of hardware, sell), support, copy and distribute through
multiple tiers  of distribution, including NORTEL distributors, a SPECIFIC
PRODUCT or FEATURE(S) solely as such INTELLECTUAL PROPERTY rights are
incorporated in such SPECIFIC PRODUCT or FEATURE(S).

4.4   ******************************************* for a *****************
**************** or ******* Manufactured by ******.

      4.4.1  SHIVA grants to NORTEL a ****************************************
license under SHIVA'S INTELLECTUAL PROPERTY to use, modify, sublicense for use
(and in the case of hardware, sell) support, copy, and distribute (with
****************** as described in the corresponding SPECIFIC PRODUCT/FEATURE
ADDENDUM) through multiple tiers of distribution, including NORTEL
distributors, a SPECIFIC PRODUCT or FEATURE(S) solely as such INTELLECTUAL
PROPERTY rights are incorporated in such SPECIFIC PRODUCT or FEATURE(S).

4.5   ****************** Distribution by ****** of ******************

      4.5.1  SHIVA grants to NORTEL a **********************************
license under SHIVA'S INTELLECTUAL PROPERTY rights to use, modify, sublicense
for use (and in the case of hardware, sell), copy, distribute through
multiple tiers of distribution, including NORTEL distributors, a SPECIFIC
PRODUCT or FEATURE(S) solely as such INTELLECTUAL PROPERTY rights are
incorporated in such SPECIFIC PRODUCT or FEATURE(S).  SHIVA shall **********
*************************** make available to any THIRD PARTY such SPECIFIC
PRODUCT or FEATURE(S).

4.6   ***************************************** for a *****************
**************** or ******************************** by ******

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      4.6.1  NORTEL grants to SHIVA a ****************************************
license under NORTEL's INTELLECTUAL PROPERTY to use, sublicense for use, copy,
distribute through multiple tiers of distribution, including SHIVA
distributors, a SPECIFIC PRODUCT or FEATURE(S) solely as such INTELLECTUAL
PROPERTY rights are incorporated in such SPECIFIC PRODUCT or FEATURE(S).

4.7   *************************** to ****************************************
for further Development pursuant to a project addendum to the MTDA

      4.7.1  NORTEL grants to SHIVA a *************************************
license under NORTEL's INTELLECTUAL PROPERTY to use a SPECIFIC FEATURE(S)
solely for the purposes of further developing NORTEL products or NORTEL
Feature(s).

4.8   Under all types of licenses, SHIVA grants NORTEL, under SHIVA's 
INTELLECTUAL PROPERTY, *************************************** license to use,
sublicense for use, copy, modify and distribute through multiple tiers of
distribution, including NORTEL distributors, DOCUMENTATION related to a
SPECIFIC PRODUCT or FEATURE(S), including release notes for updates.

4.9   SHIVA grants to NORTEL *************************************************
***************************** PRODUCTS purchased or manufactured (pursuant to
a right to ***********) and DOCUMENTATION during the term of the MARKETING
AGREEMENT.  Any alteration or use of *********************************
relating to the PRODUCTS and DOCUMENTATION shall require prior review and
approval by *****.  ****** agrees to ***** the *********************** to any
future PRODUCTS that it markets under any ********************************. 
Design of the ***************** ***** shall be subject to prior review and
approval by ******.

5.0   MARKETING CONSIDERATIONS

5.1   First Market Share Review.  On or about ******************, NORTEL's (i)
VP of Multimedia Solutions, (ii) AVP of Internet Solutions and (iii) VP of
Regional Marketing and SHIVA's (i) Senior VP of Sales and Marketing and (ii)
VP of Regional Sales and Marketing (collectively, "the SENIOR ADVISORY
GROUP") shall review performance against the MINIMUM MARKET PERFORMANCE
OBJECTIVE and the SHIVA R&D DELIVERABLES DEPENDENCIES.  In the event of
deficient performance the deficient PARTY shall identify how it proposes to
cure the deficient performance during the following **********************. 
In the event that both PARTIES are deficient the PARTIES may elect to
terminate the ********************* of the corresponding license rather than
to cure.  Upon mutual agreement only, the PARTIES may adjust the MINIMUM
MARKET PERFORMANCE OBJECTIVE and the SHIVA R&D DELIVERABLES DEPENDENCIES.  In

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the event that only one PARTY has failed to perform, that PARTY has the
unilateral right to cure for ****************.

5.2   Second Market Share Review.  On or about *****************, the SENIOR
ADVISORY GROUP shall review performance against the MINIMUM MARKET
PERFORMANCE OBJECTIVE and the SHIVA R&D DELIVERABLE DEPENDENCIES.  In the
event that both PARTIES are deficient, the PARTIES may elect to terminate the
********************* of the corresponding license or to continue the
*********************.  In the event that only one PARTY has failed to
perform, the non-breaching PARTY has a unilateral right to **********
******************* of the corresponding license.  In the event that the non
breaching PARTY elects to ******************************** of the
corresponding license in accordance with this Section 5, that PARTY shall
notify the other PARTY sixty (60) days prior to the effective date of such
**********.  In the event *********** has been terminated, each PARTY shall
be able to distribute the SPECIFIC PRODUCT or FEATURE covered by the
corresponding license, and, in the case of ******, to ******************
*************** of those THIRD PARTIES enumerated in Exhibit J to the *****
*************************************

5.3   Subsequent Market Share Reviews.  On or before ****************, and on
or before *********** for subsequent *****, the PARTIES shall establish a new
MINIMUM MARKET PERFORMANCE OBJECTIVE and SHIVA R&D DELIVERABLE DEPENDENCIES
and shall update Exhibits F and G of the MARKETING AGREEMENT accordingly.  
The PARTIES shall follow the same First Market Share Review and Second Market
Share Review process for 1998 and subsequent years, with dates revised, by
written amendment to this MARKETING AGREEMENT, as deemed appropriate, by the
PARTIES.

5.4   Sales to *******************************.  The PARTIES agree to
cooperate in establishing a transition program whereby ****** shall *******
*****************************************************************.  For a
period of time commencing on the EFFECTIVE DATE of the MARKETING AGREEMENT
and ****************************, the PARTIES agree to determine distribution
rights for ******************************* according to the process described
in this Section.

The SENIOR ADVISORY GROUP and the senior team leader of the SPG shall hold
monthly meetings to review potential ******************************* and
determine distribution rights according to the below listed guidelines.  In
no circumstance shall the lack of **************** restrict ******** pursuit
of business opportunities with these accounts.

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Guidelines

1. Demonstrable ******************.  The PARTY that ******************
*********** in the specific ****************************** and performed
*********** activities in support of the prospective account is given
preference for ******************* unless other guideline factors would
suggest a different result.

2. **************************************************.  Any expressed ********
********** shall be given the *************** in determining which PARTY
should service and support the customer.

3. ***********************************************.  The PARTIES shall review
the *************************************************************************
**************, rather than ********************************* to either
PARTY, in order to determine the best PARTY to service and support the
customer.

4.  ************************************************************.  The PARTIES
shall determine which PARTY is most likely to prepare *********************
******************************.

5.  ******************.  The PARTIES shall determine which PARTY is best able
to provide ******************.

6.  **********************************************************************
**********.  In the event a ********* or **** is involved in the transaction
and is *************************, the PARTIES shall determine the
relationship of the *********** and the **************************.  ******
shall ***************************************************.

7.  ***********************.  The PARTIES shall evaluate *********************
******************************************** to determine which PARTY has an
*********************************************************************.

The PARTIES agree that ******************************* may continue to
******************************************* when there is no involvement by
***************.  These guidelines are intended to address only those
situations where the PARTIES are determining *****************************
for PRODUCTS and sold to *******************************.

6.0   RIGHT TO MANUFACTURE (RTM) LICENSE

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6.1   SHIVA grants to NORTEL a *********************** RTM license (including,
without limitation, the right ************************************* and the
right ********************) under SHIVA'S INTELLECTUAL PROPERTY rights
(including the MANUFACTURING KNOW-HOW PACKAGE) for SHIVA's LanRover Access
Switch technology which NORTEL ********** Rapport 112 and SHIVA's Access Port
technology which NORTEL ************** Rapport Soho Router and any future
PRODUCT that the PARTIES agree to in writing and for which NORTEL pays the
agreed upon RTM FEE.  SHIVA shall make the RTM rights to any future products
available to NORTEL on similar terms and conditions ***************** as are
described in this Section 6 and Section 7.

6.2   The MANUFACTURING KNOW HOW PACKAGE shall include **************** of
SHIVA manufacturing engineering support to assist NORTEL in understanding the
contents of the MANUFACTURING KNOW HOW PACKAGE.  Additional manufacturing
engineering support is available ***************************************
******.

6.3   SHIVA shall advise NORTEL of its ********* and has made ***************
********************************** available to NORTEL.  SHIVA shall use its
best efforts to assist NORTEL in obtaining ***************************
************************************************************ (including any
and ********************************************************.  NORTEL is free
to enter into **************** with SHIVA's *********.  In the event NORTEL
uses SHIVA's ********* and requires access to ******* tools and equipment
***** shall provide technical ********** at the ***************.   Such
technical ********** shall include (i) engineering change order (ECO)
documentation, ************ and **************, (ii) ************ the
************** of any ********** components and (iii) **** and *************
******************* and *******; SHIVA shall use reasonable efforts to report
any technical ******************* to NORTEL.  SHIVA shall charge NORTEL a fee
no more than ***************** of ****************** for NORTEL's use of such
******************. In addition, ********* shall be requested to create
separate ************ for ***************.  NORTEL shall be required to
********* their ***************************************** with SHIVA
*********. SHIVA shall no longer accept Return Material Authorizations RMA's
on NORTEL manufactured product.  SHIVA shall pay for any ***********
********** with Engineering Change Orders or design changes that are *********
********.  NORTEL shall pay for any ********************** with Engineering
Change Orders or design changes that are ********************************
******.  NORTEL acknowledges that the *********** and ******** process
described in Section * shall differ from the process employed by SHIVA in the
event NORTEL ******************************.  In the event that NORTEL
********************************, NORTEL shall be responsible for ***********
************************************************************************.

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7.0   PAYMENTS FOR RTM LICENSE

7.1   NORTEL has paid a ************** RTM FEE of ************************
******************************** for the RTM license for SHIVA's LanRover
Access Switch technology which NORTEL ************** Rapport 112.  Subject to
NORTEL's acceptance of all of the ************************* Rapport 112,
including but not limited to, **********************, NORTEL shall pay a non
refundable RTM FEE of ******************************************* RTM for
**************.  Such payment shall be made ************************ from the
date that NORTEL receives an invoice for such RTM from SHIVA.  The combined
********************************************************* RTM FEE constitutes
the *********************** Rapport 112 (including the *******, associated
************* and ***********, and *************************************
Rapport 112 ***********.

7.2   ********************************** Access Switch ********************.
Upon NORTEL's acceptance of the performance and functionality of the **,
NORTEL shall pay a ************** RTM FEE of ************************
******************************** for a RTM license for the **********
************************.  Subject to the acceptance of the performance and
functionality of the **, such payment shall be made ******************* from
the date that NORTEL receives an invoice for the ** RTM FEE.

7.3	Rapport **** Router.  NORTEL has paid SHIVA a ************** RTM FEE of
****************************************** for a license to manufacture the
Access Port technology which NORTEL ******* as the Rapport ***********.  The
RTM FEE included the **************** to ******* the ******************
****************************.  In the event that SHIVA, in its sole option,
selects NORTEL as the ******************* SHIVA Access Port, ***************
***************************** RTM FEE shall be ********.

8.0   TRAINING

8.1   NORTEL CUSTOMER Training Courses. SHIVA agrees to provide technical
support training and a "Train the Trainer" program to NORTEL as outlined in
Exhibit D. ******* for training are assessed apart from the *************
******* described in Exhibit D including ************** "Train the Trainer"
course **********************************************************. SHIVA
grants to NORTEL, in exchange for this ************, a ********* license to
use, copy, modify and distribute SHIVA'S training materials under NORTEL's
************************************************ for the purposes of
providing training to *********************************** and *********.
SHIVA agrees to provide the course materials in an electronic format
compatible with NORTEL's current training documentation.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

8.2   NORTEL Support Training. SHIVA agrees to provide NORTEL with additional
training courses at NORTEL's request at *******************************
************** at SHIVA'S training facility. For courses away from SHIVA'S
training facility, NORTEL agrees to pay *******************************
**************************************************************************
******* SHIVA employees providing such courses. SHIVA further agrees that
NORTEL shall be entitled to receive further ************* training prices,
should SHIVA **********************************************************.

9.0   SHIVA ********************* PRODUCT(S) ** NORTEL

9.1   Purchase Price.  All purchase prices are ****************************.
SHIVA agrees to sell, and NORTEL agrees to purchase PRODUCTS, **************
*************************************************************************
***********

(a)   *****************************************************************
************
(b)   *********************************************************************
****************************************************************************
********************* CARRIER/ISP).

9.2   Price and Cost Revisions - SHIVA shall provide NORTEL with at least
************************************** of any changes in the list price for
******************************************, and if possible, ****************
**************.  Any price reductions shall be applied to ***********
**************************************************************************
***********************************************************************
*********.  SHIVA agrees that it: (i) shall use reasonable efforts to ******
********************** and ********************** throughout the term of the
MARKETING AGREEMENT; (ii) shall proportionally ****************************
******************* to reasonably reflect any substantial reduction in the
***************************************, and (iii) shall *****************
*************************************************************************
************************************************************************
****************************************************************************
******************************************.  In the event of SHIVA's breach
of its ************************** set forth herein, SHIVA shall **********
***************************************************************************
*****************************************************************************
*****************************************************************.

9.3   Order and Acceptance.  All orders placed by NORTEL under the MARKETING
AGREEMENT shall be initiated by a written purchase order requesting a
delivery date; provided, however, that an order may be placed by facsimile.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

if a confirming hard copy of the written purchase order is received by SHIVA.
SHIVA shall notify NORTEL of the acceptance or rejection of an order and of
the assigned delivery date for accepted orders within a reasonable time ***
******************************** after receipt of the written or oral
purchase order. SHIVA shall maintain an adequate inventory of PRODUCTS to
meet the forecasts provided under the MARKETING AGREEMENT and shall use its
reasonable efforts to deliver the PRODUCTS at the times specified either in
the purchase order or as otherwise mutually agreed by the PARTIES. The
expectation is that SHIVA shall ship the PRODUCTS to **********************
***************************** complete and shippable order from NORTEL.

9.4   Forecast.  During the term of the MARKETING AGREEMENT, NORTEL shall
provide a ***************** rolling forecast of PRODUCT purchases to SHIVA.
The first ************** shall be forecasted ******** and ****************
****** shall be forecasted ********** for the PRODUCTS.  This forecast
information shall include at a minimum, the PRODUCTS required, the quantities,
and the month of planned shipment to NORTEL.

      SHIVA shall use NORTEL's forecast information to manage its inventory so
as to be able to deliver the forecasted-demand within the time frame described
in this Section. The PARTIES shall work together to manage any variations
from the forecast.  NORTEL shall provide a single point of contact for SHIVA
to work with to manage the supply and forecast process.

      NORTEL shall issue **********************************************
************************************************************.  In the event
NORTEL's purchase orders exceed the demand forecast, SHIVA agrees to increase
production and/or delivery by ******************************************
************************************ (3), **********************************
*****************************************************
      Time Frame               Demand Forecast Up-Side
      ************************************
      ************************************
      ************************************
      ************************************

      In all cases where purchase orders exceed the demand forecast, SHIVA
shall provide best effort to meet purchase order requirements within a
reasonable time frame.  All increases to the demand forecast shall be
formally committed to by SHIVA within ************************ receipt of
purchase orders which exceed the demand forecast.

      For the purpose of ordering material with long lead-times, SHIVA shall
use the demand forecast.  In the event material unique to NORTEL with long
lead-times is required to support the demand forecast, subject to NORTEL

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

prior approval, SHIVA shall order such long lead-time material. NORTEL agrees
to reimburse SHIVA for the added cost of procuring such material.  Unique
material shall include NORTEL customized corrugated boxes or packaging,
labels for packaging, documentation, overlays for PRODUCTS, and software
media. SHIVA agrees to use best effort to minimize NORTEL's liability for
such material by canceling orders, returning material for credit or reworking
/ utilizing common material into other server PRODUCTS.  Additionally, SHIVA
shall provide to NORTEL documentation in support of any claim made under this
Article.

9.5   Shipping.  All PRODUCTS delivered pursuant to the terms of the MARKETING
AGREEMENT shall be packed as commercially necessary for successful shipment
and marked for shipment and delivered to *************************************
**********. Upon delivery to ****************, ************ to the PRODUCTS
*****************************************************.

9.6   Payment.  **** payment of the purchase price for PRODUCTS shall be made
by NORTEL, ************************ from the date that NORTEL receives (i)
the PRODUCT or (ii) an invoice for such PRODUCTS.

9.7   Rescheduling.  NORTEL may reschedule any delivery date at any time prior
to the date of shipping *************************************** provided that
the rescheduled delivery date is within the calendar quarter.

9.8   Quality Commitments.  The PARTIES agree within **************** from the
EFFECTIVE DATE, to develop a quality improvement plan to improve PRODUCT
supplied to NORTEL by SHIVA.  Upon implementation of the quality improvement
plan, SHIVA agrees to abide by such plan to maintain a minimum quality level
of ********************************* in PRODUCT shipped to NORTEL as
evidenced by NORTEL's system test and field installation results.

9.9   Inspection and Acceptance.  The acceptance of PRODUCT purchased from
SHIVA is subject to inspection by NORTEL at its delivery location and such
acceptance shall be deemed to occur **************** after receipt of such
PRODUCTS at NORTEL's delivery location unless NORTEL shall have provided
SHIVA with notice of non-acceptance within such period.

      PRODUCTS will be inspected by NORTEL for major defects, with major
defects being defined as (i) any ******************, or (ii) a ***********
***********************************************************************
********************, or (iii) a ****************************************
**********************************************************.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

      If any unit of PRODUCT does not conform to the requirements of a
purchase order or release of a purchase order or to the warranties set forth
in Article 11, as determined by NORTEL's inspection pursuant to the terms
stated in this Section 9.9, ***********************************************
may be returned to SHIVA ******************.  Payment shall neither be deemed
to constitute acceptance nor be a **************************************
*********************************************.

9.10  ********************.  NORTEL agrees to purchase from SHIVA a cumulative
total of **************************************** Rapport 112 ************
***************************************************************************. 
**** payment for such purchase shall be made ******************* from the
date that NORTEL receives (i) such Rapport 112 product and (ii) an invoice
for such Rapport 112 product.  SHIVA agrees to ***********************
****************************************************************** which mean
those ***************************** that makes ******************************
*****************************************************************************
**********.  The ******************** for ************** shall only apply
until *****************, at which time such ******************.  The
******************** for the cumulative ********** in purchases shall apply
only to the extent that NORTEL consumes such inventory of purchased PRODUCT
for sales on a first in first out basis.  For ************************ SHIVA
may direct NORTEL **************** to other SHIVA channels for Enterprise
market applications globally.  In any case, with respect to *************
**********, NORTEL would ***********************************************
*********** SHIVA **************************** to be ***********************
************************************** in the event that SHIVA ******* the
**********, SHIVA shall ***************** NORTEL for ********************
********* based on the ********* on the SHIVA ********** and the ********
*******************************.

10.0  SUPPORT

10.1  NORTEL Support Obligations.  NORTEL shall generally provide first and
second level support to CUSTOMERS. NORTEL shall access SHIVA support
resources through NORTEL's Global Technical Support (GTS) group, currently
located in Ottawa, Canada. NORTEL GTS shall provide problem descriptions and
customer information in a format which shall be mutually agreed with SHIVA.

10.2  SHIVA Support Obligations.  SHIVA shall provide support to NORTEL as set
forth in Exhibit D. NORTEL agrees to pay SHIVA according to the terms
described in Exhibit D for support during the term of the MARKETING
AGREEMENT. 

<PAGE>  17

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

10.3  Customer Requests.  In the event that the CUSTOMER requests support
terms that would require the PARTIES to provide additional services or rights
(such as support availability guarantees or customer escrow arrangements),
the PARTIES shall work together to provide such customer with additional
support terms that are acceptable to the CUSTOMER and to both PARTIES.

11.0  WARRANTY

11.1. General.  SHIVA warrants that (i) it has all INTELLECTUAL PROPERTY
rights including any INTELLECTUAL PROPERTY rights in any THIRD PARTY
technology necessary to permit NORTEL to exercise all rights granted to it
under the MARKETING AGREEMENT, (ii) any hardware PRODUCT manufactured by
SHIVA and delivered to NORTEL for **************************************
shall conform to SPECIFICATION(S) for a period of ***********************
from the date of delivery to NORTEL, and (iii) any hardware PRODUCT
manufactured by SHIVA and delivered to NORTEL for CUSTOMERS, not including
**************************************, shall conform to SPECIFICATION(S) for
a period of ******************** from the date of delivery to NORTEL.  The
SOFTWARE delivered pursuant to the MARKETING AGREEMENT shall be warranted for
a period of *************************.  The PARTIES agree that major SOFTWARE
defects shall be dealt with according to the terms described in the MTDA. 
SOFTWARE defects that become apparent following FCS of the SOFTWARE shall be
remedied according to the terms specified in Exhibit D.  NORTEL agrees to
consolidate all repair PRODUCTS from the field, whether under warranty or
not, and ship to a central SHIVA site. SHIVA'S sole responsibility under this
warranty shall be, at SHIVA's option, to either repair or replace the PRODUCT
within ************* and ship the replacement PRODUCT to NORTEL.  SHIVA
warrants the repaired PRODUCTS shall conform to SPECIFICATION(S) for (i) a
period of **************** from the date of delivery to NORTEL or (ii) the
remainder under the original warranty, whichever is longer.  For PRODUCTS
returned for repair that fall outside the warranty period, SHIVA shall
provide the same service to NORTEL as for items under warranty, and NORTEL
shall pay SHIVA for the repair service.  SHIVA shall provide NORTEL with a
repair price list prior to NORTEL's FCS of any PRODUCT and update the list
quarterly for any changes.  The repair price list shall reflect SHIVA's
associated cost and overhead to repair the defective part.  In the event that
a PRODUCT has a material defect before NORTEL ships such PRODUCT to its
CUSTOMERS, the warranty period shall ********* until SHIVA has provided
NORTEL with a replacement that is (1) a ******** or *********, and (2) ****
*******************.  SHIVA reserves the right to charge NORTEL for *********
************************ PRODUCTS that are returned to SHIVA for repair.

11.2  Class A Changes.  During the term of the MARKETING AGREEMENT and
thereafter for **************, in the event that the PRODUCTS supplied by

<PAGE>  18

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

SHIVA under the MARKETING AGREEMENT, including, but not limited to, NORTEL's
inventory on hand manufactured by SHIVA, but excluding PRODUCTS manufactured
by or for NORTEL have a material design defect that causes either (i)
***************************, or (ii) ***************************************
**********, SHIVA shall immediately evaluate the problem and as expeditiously
as possible provide any change necessary to the component to correct the
problem ("Class A Change").  SHIVA shall be responsible for providing all
necessary instructions, materials and labor to implement Class A Changes on
SHIVA's premises.

11.3. Limitations.  Neither PARTY shall have any obligation to provide
services under this Article if material defects are caused by (i) malfunction
of THIRD PARTY hardware or software other than such THIRD PARTY content as is
included by the providing PARTY as part of PRODUCT(S) or FEATURE(S) that are
the subject of this MARKETING AGREEMENT, (ii) modification not made or
specified by such PARTY, (iii) operator error or (iv) use that is not in
accordance with applicable operating instructions.

11.4  Year 2000 Warranty.

      11.4.1  SHIVA represents and warrants that by January 1, 1998, all
PRODUCTS and FEATURES provided pursuant to this MARKETING AGREEMENT, when
used in accordance with their SPECIFICATIONS and DOCUMENTATION, shall (i)
process date and time related data without causing any processing
interruptions, abnormal terminations, or changes in performance
characteristics, and (ii) shall process and manipulate all date and time
related functions correctly.  Without limiting the generality of the
foregoing, all PRODUCTS and FEATURES provided by SHIVA shall:

              (a) correctly handle date and time related data before, during
and after January 1, 2000, including but not limited to accepting date input,
providing date output, and performing ongoing operations on dates and
portions of dates including, but not limited to, calculating, comparing and
sequencing of dates (in both forward and backward operations spanning century
boundaries);

              (b) correctly handle leap year calculations (including but not
limited to identification of leap years, interval calculations, day-in-year
calculations, day-of-the-week calculations, and week-of-the-year
calculations);

              (c) correctly handle all two digit date and time related input
in a manner that resolves ambiguity as to century in a disclosed, defined and
predetermined manner; and

<PAGE>  19

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              (d) correctly store and provide output of all date and time data
in a manner that is unambiguous as to century.

      11.4.2  SHIVA shall immediately notify NORTEL of any and all date-
related bugs, errors or deficiencies in the PRODUCTS and/or SHIVA supplied
FEATURES.  For the purpose of problem resolution, any such date related bugs,
errors or deficiencies shall be deemed to be bugs, errors or deficiencies of
the highest priority level, and shall be resolved according to the procedures
provided for such priority level. 

      11.4.3  Any provisions of the MARKETING AGREEMENT that tend to limit or
eliminate the liability of SHIVA shall have no application with respect to
the year 2000 compliance warranty set out above.

11.5  LIMITATION OF LIABILITY.  IN NO CASE SHALL EITHER PARTY BE RESPONSIBLE
TO THE OTHER FOR ANY SPECIAL, CONSEQUENTIAL, INCIDENTAL, OR INDIRECT DAMAGES
HOWEVER CAUSED. EXCEPT FOR THE LIABILITIES OF EITHER PARTY UNDER
CONFIDENTIALITY, INDEMNIFICATION AND LIABILITY AND SECTION 11.4 ONE PARTY'S
LIABILITY TO THE OTHER SHALL IN NO INSTANCE EXCEED ***********.

11.6. Disclaimer.  EXCEPT FOR THE WARRANTIES SPECIFICALLY STATED IN THE
MARKETING AGREEMENT, SHIVA HEREBY DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR
IMPLIED, INCLUDING ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE.

12.0  SALES AND MARKETING AND SUPPORT - SERVICE PROVIDER GROUP

12.1  The intent of SPG is to increase NORTEL sales into the *********
CARRIER/ISP MARKET.  The management structure, functions and mode of
operations between NORTEL and SPG are described in Exhibit I.

12.2  NORTEL agrees to pay SHIVA to fund SPG for not more than ***************
********************************************************************* for not
more than **************** people and **********************************
***********************************************************************
***************** people.  Funding requirements for subsequent quarters shall
be reviewed for approval by the last day of the first month of the preceding
quarter.  Subject to such review and if approved, NORTEL shall pay SHIVA to
fund SPG for not more than *************** people in the ****************
**** and for not more than ********** people in the **********************. 

<PAGE>  20

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NORTEL shall pay for the actual costs incurred by the SPG on a monthly basis
************************ subject to the quarterly caps outlined above and as
subsequently established by the PARTIES.  In no event shall NORTEL be
responsible for any costs in a quarter which exceed the established quarterly
cap for such quarter.  Shiva agrees to control internal costs within an
agreed upon budget. 

12.3  SHIVA shall maintain complete and accurate records of all expenditures
made or incurred in respect of the SPG.  Such records shall be maintained in
accordance with generally accepted accounting principles.  SHIVA shall retain
such records for the preceding seven (7) years.

Upon thirty (30) days notice to SHIVA, NORTEL may request an audit of the SPG
by an independent auditor reasonably acceptable to SHIVA.  During the period
in which SHIVA is required to maintain SPG records, such auditors shall have
reasonable access to such records at a mutually agreeable time and location
for the purposes of conducting an audit.

NORTEL shall bear all audit expenses unless such audit reveals that SHIVA has
overstated its expenditures in respect of the SPG by more than ***********
*****, in which case SHIVA shall pay all reasonable costs associated with the
audit.  Prompt adjustment shall be made to compensate for any overstatement
of expenses revealed by the audit.

12.4  Neither SHIVA, nor any of its employees or agents, shall, in any sense,
be considered employees or agents of NORTEL, nor shall SHIVA, its employees
or agents, be eligible or entitled to any benefits, perquisites or privileges
given or extended to NORTEL employees.

12.5  SHIVA represents and warrants to NORTEL that SHIVA shall be solely
responsible for: (i) compensating each of its employees performing SPG
services under the MARKETING AGREEMENT; (ii) withholding any sums from
amounts payable to such employees with respect to federal, state or local
taxes, FICA contributions, unemployment insurance, or similar matters; and
(iii) paying all such amounts to the appropriate entity.

13.0  CONFIDENTIALITY, PROPRIETARY NOTICES AND LEGENDS

13.1  Confidential Information.  Each PARTY may receive, under the terms of
the MARKETING AGREEMENT, proprietary, scientific, technical, planning,
business, marketing, product or financial information, formulas, patterns,
compilations, programs, devices, methods, techniques, processes, data, trade
secrets or know-how (hereinafter "INFORMATION") of a PARTY or its
SUBSIDIARIES or AFFILIATES which is designated as confidential or similar
designation at the time of disclosure or that would be understood by the
PARTY receiving such INFORMATION at the time of disclosure, exercising

<PAGE>  21

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

reasonable business judgment, to be confidential (hereinafter "CONFIDENTIAL
INFORMATION").  The receiving PARTY shall at all times during the term of the
MARKETING AGREEMENT, and for ten (10) years after the termination of the
MARKETING AGREEMENT, hold such CONFIDENTIAL INFORMATION in confidence and not
disclose to THIRD PARTIES except for temporary workers or other contractors
who have been retained by a PARTY pursuant to an agreement that contains
appropriate confidentiality provisions.  The receiving PARTY shall protect
the CONFIDENTIAL INFORMATION of the disclosing PARTY to the same extent as it
protects its own information of similar type but shall use no less than
reasonable care.  These obligations shall not apply to information which: (i)
was in possession of, or was known by the receiving PARTY prior to its
receipt from the disclosing PARTY; (ii) is or becomes public knowledge
without the fault of the receiving PARTY; (iii) is received by the receiving
PARTY without restriction on disclosure, from a THIRD PARTY who disclosed the
information not in violation of any confidentiality restriction or (iv) is
disclosed by the receiving PARTY pursuant to statute, regulation, or the
order of a court of competent jurisdiction, provided the receiving PARTY
previously notifies the disclosing PARTY to permit the taking of appropriate
protective measures.  The CONFIDENTIAL INFORMATION provisions contained in
the MARKETING AGREEMENT shall apply to INFORMATION exchanged between the
PARTIES pursuant to prior agreements, or in anticipation of this MARKETING
AGREEMENT.

14.0  ******

      For PRODUCTS that are the subject of this MARKETING AGREEMENT, SHIVA
shall promptly deposit with a THIRD PARTY acceptable to both SHIVA and NORTEL
***************************************************************************,
to the extent not previously supplied to NORTEL pursuant to a RTM license,
the ************************************************************************
all of which may be required for a **************************************
****************.  NORTEL shall pay *******************. Neither PARTY shall
terminate ********************** without the prior written consent of the
other PARTY.  The **************** shall provide that in the event that (i)

<PAGE>  22

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

***********************, or ************************, (ii) ***************
******* PRODUCTS ** NORTEL for ******************** according to the terms of
the MARKETING AGREEMENT, or (iii) **********************************
****************************************************************************
********************************************************************MARKETING
AGREEMENT ************************************************ MTDA, **********
********************************************* NORTEL subject to a license
that is intended to supplement if required but not supersede any other
license rights granted to NORTEL in this MARKETING AGREEMENT, **********
****************** according to the following terms.  In the event of release
********************* due to (i) and (ii) NORTEL may use *************
********************************************** but may not *****************
*********************************.  In the case **************************
**************** (iii) *****************************************************
***********************.  Additionally, ********** agreement shall provide
that (i) NORTEL may continue to ********************************************
********* (ii) ********************* NORTEL's ******, NORTEL ***************
*****************************************************************************
*************************************************************************
****************************************************************************
*****************************************************************************
***********************************************.

15.0  INDEMNIFICATION AND LIABILITY

15.1  Indemnification.  SHIVA shall defend, at its expense, any action brought
against NORTEL, NORTEL's distributors, NORTEL's SUBSIDIARIES, NORTEL's
AFFILIATES and CUSTOMERS to the extent that it is based on a claim or
threatened claim that the manufacture, use or sale of the PRODUCTS infringe
any copyright, patent, trademark, mask work or trade secret or other
INTELLECTUAL PROPERTY right and SHIVA shall indemnify and hold NORTEL,
NORTEL's distributors, NORTEL's SUBSIDIARIES, NORTEL's AFFILIATES and
CUSTOMERS harmless from any costs, damages, settlements and fees (including
reasonable legal fees and expenses) incurred by NORTEL, NORTEL's
distributors, NORTEL's SUBSIDIARIES, NORTEL's AFFILIATES and CUSTOMERS in
such action which are attributable to such claim or threatened claim provided
that NORTEL notifies SHIVA promptly in writing of any claim, permits SHIVA to
defend, compromise or settle the claim and provides all reasonably available
information and assistance regarding such claim. SHIVA shall not be liable
for any costs, damages, or fees incurred by NORTEL, NORTEL's distributors,
NORTEL's SUBSIDIARIES, NORTEL's AFFILIATES and CUSTOMERS in the defense of
such action or claim unless authorized in writing by SHIVA.  Should any
PRODUCTS become, or in SHIVA's reasonable opinion be likely to become, the
subject of a claim for infringement of such copyright, patent, trademark,
mask work or trade secret or other INTELLECTUAL PROPERTY rights, SHIVA may
(i) procure for NORTEL, at no cost to NORTEL, NORTEL's distributors, NORTEL's
SUBSIDIARIES, NORTEL's AFFILIATES and CUSTOMERS the right to continue to use
the PRODUCTS, (ii) replace or modify the PRODUCTS at no cost to NORTEL,
NORTEL's distributors, NORTEL's SUBSIDIARIES, NORTEL's AFFILIATES and
CUSTOMERS, to make such non-infringing, provided that the replacement or
modified PRODUCTS provides equivalent function and performance; or (iii) if
neither (i) or (ii) are commercially feasible, terminate the right to use
such PRODUCTS, remove the PRODUCTS, refund to NORTEL all monies paid by

<PAGE>  23

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NORTEL to SHIVA in respect of such PRODUCTS, and cancel any further
obligations NORTEL may have under the MARKETING AGREEMENT in respect of such
PRODUCTS.  This Section states the entire liability with respect to
infringement of any THIRD PARTY INTELLECTUAL PROPERTY rights and neither
PARTY shall have additional liability with respect to any alleged or proven
infringement.

15.2  NORTEL and SHIVA each agree to indemnify, defend and hold harmless the
other PARTY, and that PARTY'S SUBSIDIARIES, AFFILIATES, officers, directors,
employees, agents, successors, and assigns, from any and all liabilities and
threatened liabilities arising from, in connection with, or based on
allegations of, any of the following:  (i) the death or bodily injury of any
agent, employee, customer, business invitee, or business visitor or other
person caused by the tortious conduct of the indemnitor; (ii) the damage,
loss or destruction of any real or tangible personal property caused by the
tortious conduct of the indemnitor; and (iii) any claim, demand, charge,
action, cause of action, or other proceeding asserted against the indemnitee
but resulting from an act or omission of the indemnitor in its capacity as an
employer of a person, including alleged or actual employment discrimination
and wrongful termination actions. 

15.3  Both NORTEL and SHIVA shall maintain, during the term of the MARKETING
AGREEMENT, all insurance and/or bonds required by any applicable law,
including, but not limited to:  (a) workers' compensation insurance as
prescribed by the laws of all jurisdictions in which work pursuant to the
MARKETING AGREEMENT is performed; (b) employers' liability insurance with
limits of at least Five Million Dollars ($5,000,000.00) per occurrence; (c)
comprehensive general liability insurance (including products liability
coverage, contractual liability, advertising liability, and comprehensive
automobile liability coverage) each coverage with limits of at least Five
Million Dollars ($5,000,000.00) per occurrence.  A PARTY shall furnish
certificates or other adequate proof of such insurance to the other PARTY
upon written request by the other PARTY.

16.0  TERM AND TERMINATION

16.1  Term.  The term of the MARKETING AGREEMENT is three (3) years from the
EFFECTIVE DATE.  The MARKETING AGREEMENT shall continue in force for the term
unless terminated earlier under the provisions of this Article 16. SHIVA'S
support obligations under the MARKETING AGREEMENT shall continue for an
additional seven (7) years after the initial term has expired.

16.2  Termination for Cause.  In the event of any material breach of the
MARKETING AGREEMENT, the non-breaching PARTY may terminate the MARKETING
AGREEMENT by giving *************** prior written notice to the other PARTY;
provided, however, that the MARKETING AGREEMENT shall not terminate if the
other PARTY has cured the breach prior to the expiration of such **********

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CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

*** period, or if such breach cannot be cured within such **************
period, the other PARTY has initiated within such ************** period
actions to cure such breach, and thereafter cures such breach as soon as
reasonably practical.  In the event the MARKETING AGREEMENT is terminated due
to SHIVA's breach for not providing PRODUCTS to NORTEL for purchase or
services according to the terms of the MARKETING AGREEMENT, ************
********* shall be ****************** pursuant to **********.  Unless
otherwise stated in a SPECIFIC PRODUCT/FEATURE ADDENDUM, in the event the
*********** provisions set forth in a SPECIFIC PRODUCT/FEATURE ADDENDUM ***
**********, NORTEL shall be entitled to *************************************
******************************** as described below.

      Any ************************* NORTEL to SHIVA in respect of a SPECIFIC
PRODUCT or FEATURE which ****************************** SHIVA *************
*********************************** (as described in the corresponding
SPECIFIC PRODUCT/FEATURE ADDENDUM) for such SPECIFIC PRODUCT or FEATURE shall
be ***************** NORTEL ******************************* NORTEL ********
such SPECIFIC PRODUCT or FEATURE ********************* as described in the
SPECIFIC PRODUCT/FEATURE ADDENDUM.

16.3  Termination for Insolvency.  Either PARTY may terminate the MARKETING
AGREEMENT in the event the other PARTY: (i) admits in writing its inability
to pay its debts generally as they become due; (ii) commits an act of
bankruptcy, (iii) files a notice of intention to make a proposal under the
Bankruptcy and Insolvency Act, commences proceedings under the Companies'
Creditors Arrangement Act, or otherwise seeks a reorganization, adjustment or
composition under applicable bankruptcy laws or any other similar law or
statute of any relevant jurisdiction; (iv) enters into an assignment,
arrangement or composition for the benefit of its creditors; or (v) consents
to the appointment of a receiver or receiver-manager of itself or of the
whole or any substantial part of its property. In the event the MARKETING
AGREEMENT is terminated due to SHIVA's **********************************
**************************************************.

16.4  Effect of Termination or Expiration.  In the event the MARKETING
AGREEMENT is terminated or expires, the following license rights shall remain
in effect:

       (i)  CUSTOMER Rights. All sublicenses properly granted by either PARTY
for the PRODUCTS or FEATURES prior to the date of the termination shall
continue in full force and effect.

<PAGE>  25

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

      (ii)  License Rights. All licenses granted by each PARTY to the other
PARTY under Exhibit E shall continue in full force and effect for an
indefinite period of time, subject to the following:

            1.  A PARTY seeking to obtain a ************* license has met the
************************ for a particular major revision of SOFTWARE related
to SPECIFIC PRODUCT(S) as such ************************ is described in
Section 16.5 below; or

            2.  A PARTY continues to make royalty payments of ***********
************************ to the granting PARTY.

            3.  NORTEL shall be granted a ********** up license, in the event
SHIVA ***********************************************************
***************************************************************************
**************** breaches the MARKETING AGREEMENT or is in breach of its
obligations under the MTDA.  In the event of such breach by **********
***********************************************************************
**********************.

      (iii) Rights to Manufacture.  All Rights to Manufacture granted under
Article 6.0 shall continue in full force and effect for an indefinite period
of time and are perpetual, fully paid up rights.

16.5  ************************

      The PARTIES shall agree upon the SPECIFICATION for each major revision
of SOFTWARE related to SPECIFIC PRODUCT(S).  Once the revision has been
agreed to by the PARTIES, the PARTY that develops the SOFTWARE must be paid
******************************************** in royalty payments by the other
PARTY in order to obtain a ************* license for such revision.  This
**************************************************************************
**************** from and modify the ****** code of the SOFTWARE.  The
PARTIES anticipate that one ************************************************
****************************************************************************
************************ for each major revision.  In no event may the
****************************************************************************
**********************************************************.  NORTEL shall
only be able to *********************************************************
*****************************************************************************
****************************************************************************

<PAGE>  26

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

*****.  NORTEL shall be entitled to *****************************************
***************************************************************************
*****************************************************************************
**********************************************************************
*************************************.  This payment shall be paid in equal
***********************************************************************
******************.

17.0  GENERAL

17.1  Governing Law.  The MARKETING AGREEMENT shall be governed in all
respects by the laws of Ontario and the federal laws of Canada applicable
therein.

17.2  Currency.  All currency amounts in the MARKETING AGREEMENT are
denominated in U.S. dollars.

17.3  Transfer Rights.  Neither PARTY shall assign the MARKETING AGREEMENT to
any THIRD PARTY (except a SUBSIDIARY) without the prior written consent of
the other PARTY; provided however, the merger or consolidation of one PARTY
into, or the sale of all or substantially all of the assets of such PARTY to,
a THIRD PARTY shall not be deemed to be an assignment. The MARKETING
AGREEMENT shall be binding upon and inure to the benefit of the PARTIES
hereto and their permitted successors and assigns and provided that the
assigning PARTY shall remain fully responsible for all of its obligations
under the MARKETING AGREEMENT unless the other PARTY has expressly agreed in
writing to release the assigning PARTY from such obligations.

17.4  Notices.  All notices or reports permitted or required under this
MARKETING AGREEMENT shall be in writing and shall be delivered by personal
delivery, facsimile transmission or by certified or registered mail, return
receipt requested, and shall be deemed given upon personal delivery, five (5)
days after deposit in the mail, or upon acknowledgment of receipt of
electronic transmission.  

Notices to SHIVA shall be sent to the Corporate Secretary at :

       Shiva Corporation
       28 Crosby Drive
       Bedford, MA 01730-1437
       Attn.:  Corporate Secretary

Notices to NORTEL shall be sent to:

       NORTHERN TELECOM, INC.
       2221 Lakeside Blvd.
       Richardson, Texas 75082
       Attn.:  AVP, Internet Solutions

<PAGE>  27

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

       NORTHERN TELECOM INC.
       2305 Mission College Blvd.
       Santa Clara, California
       Attn.:  Sr. Manager, Enterprise Licensing

cc:    Northern Telecom Limited 
       8200 Dixie Road, Suite 100
       Brampton, Ontario  Canada  L6T 5P6
       Attn.:  Manager, Technology Law and Licensing

17.5  No Agency.  Nothing contained herein shall be construed as creating any
agency, joint venture, partnership, or other form of joint enterprise between
the PARTIES.

17.6  Force Majeure.  Neither PARTY shall be liable by reason of any failure
or delay in the performance of its obligations hereunder (except for the
payment of money) on account of strikes, shortages, riots, insurrection,
fires, flood, storm, explosions, acts of God, war, governmental action, labor
conditions, earthquakes, or any other cause which is beyond the reasonable
control of such PARTY.  If such delays continue for more than sixty (60)
consecutive days then either PARTY may elect to terminate this MARKETING
AGREEMENT with no further obligations on either PARTY.  In the event the
MARKETING AGREEMENT is terminated as provided in this Section, NORTEL shall
be entitled to credit any future royalty obligations against advance royalty
payments as described.

      ***************************** NORTEL ** SHIVA in respect of a SPECIFIC
PRODUCT or FEATURE which ****************************** SHIVA *************
*********************** calculation (as described in the corresponding
SPECIFIC PRODUCT/FEATURE ADDENDUM) for such SPECIFIC PRODUCT or FEATURE shall
be ************************************************************************
******************************************************.

17.7  Waiver.  The failure of either PARTY to require performance by the other
PARTY of any provision hereof shall not affect the full right to require such
performance at any time thereafter; nor shall the waiver by either PARTY of a
breach of any provision hereof be taken or held to be waiver of the provision
itself.

17.8  Severability.  In the event that any provision of the MARKETING
AGREEMENT shall be unenforceable or invalid under any applicable law or be so
held by applicable court decision, such unenforceability or invalidity shall
not render the MARKETING AGREEMENT unenforceable or invalid as a whole, and,
in such event, such provision shall be changed and interpreted so as to best

<PAGE>  28

accomplish the objectives of such unenforceable or invalid provision within
the limits of applicable law or applicable court decisions.

17.9  Entire Agreement.  The MARKETING AGREEMENT and the Exhibits constitute
the entire agreement between the PARTIES with respect to the subject matter
hereof.  The MARKETING AGREEMENT supersedes, and the terms of the MARKETING
AGREEMENT govern, any prior or collateral agreements, including but not
limited to the agreement between the PARTIES dated May 15, 1995 and all
subsequent amendments, with respect to the subject matter hereof (but does
not supersede the MTDA between the PARTIES which deals with related subject
matter).  In the event of a conflict between the MARKETING AGREEMENT and the
MTDA, the MARKETING AGREEMENT shall govern.  The MARKETING AGREEMENT may only
be changed by mutual agreement of authorized representatives of the PARTIES
in writing.

17.10 Survivability.  Sections 1, 2, 4, 6, 11, 13 ,15, 16, and Section 17.10,
17.12 and any corresponding parts of the exhibits referenced in such Sections
shall survive termination of this MARKETING AGREEMENT.

17.11 Except for any announcement intended solely for internal distribution by
the PARTIES or any disclosure required by legal, accounting or regulatory
requirements beyond the reasonable control of the PARTIES, all media
releases, public announcement or public disclosures (including, but not
limited to, promotional or marketing material) relating to the MARKETING
AGREEMENT or its subject matter shall be coordinated with and approved in
writing by both PARTIES prior to the release thereof.

17.12 Both PARTIES shall keep reasonable, proper records relating to: Sections
2.2, 3.1, 5.1, 5.2, 6.3, 8.2, 9.2, 9.4, 11.1, 12.2, Exhibit D, Exhibit E,
Exhibit H and Exhibit I for seven (7) years after the termination of the
MARKETING AGREEMENT.  A chartered or certified public accountant selected by
either PARTY may, upon reasonable notice, during normal business hours, but
not more than once a year, inspect the reporting PARTY's records as is
necessary to verify the accuracy of the reporting PARTY's charges and/or
pricing pursuant to Sections 2.2, 3.1, 5.1, 5.2, 6.3, 8.2, 9.2, 9.4, 11.1,
12.2, Exhibit D, Exhibit E, Exhibit H and Exhibit I.

17.13 Employee Restrictions.  During the term of the MARKETING AGREEMENT, and
for a period of one (1) year thereafter, neither PARTY, without the prior
written consent of the other PARTY, shall solicit or employ any employee of
the other PARTY who is responsible for completing obligations of the other
PARTY under the MARKETING AGREEMENT or the MTDA.

17.14 Export Compliance.  The rights and obligations of the PARTIES may be
subject to United States and Canadian laws and regulations governing the

<PAGE>  29

license and delivery of technology abroad by persons subject to the
jurisdiction of the United States and Canada, including the Export
Administration Act of 1979, as amended, and the Export Administration
regulations issued by the US Department of Commerce, International Trade
Administration, Office of Export Administration. Each PARTY shall not,
directly or indirectly, export, reexport or transship technology, software,
components or PRODUCTS, in such manner as to violate such laws and
regulations in effect from time to time to the extent that such laws are
applicable to a PARTY.

17.15 NAFTA.

      (i)  Administrative Actions. Both PARTIES shall perform all
administrative actions required to qualify each PRODUCT sold under the
MARKETING AGREEMENT for preferential treatment under the rules of any
applicable trade treaty, including, without limitation, NAFTA. If a PRODUCT
qualifies under NAFTA, the PARTY shall prepare and distribute a NAFTA
Certificate of Origin, and any other documents required. The PARTIES shall
respond to requests from the other PARTY for information regarding any NAFTA
Certificate of Origin and assist each other in resolving any eligibility
issues.

      (ii) Certificate of Origin. If a NAFTA Certificate of Origin is prepared
for each shipment, each PARTY shall: (a) retain the original NAFTA
Certificate of Origin with appropriate backup documentation, (b) attach a
copy of the NAFTA Certificate of Origin to the customs/shipping documents for
the qualifying component or PRODUCT, and (c) mark the customs/shipping
documents with the legend: "Copy of NAFTA Certificate of Origin attached." If
a blanket NAFTA Certificate of Origin is prepared, the PARTIES shall: (a)
retain the original NAFTA Certificate of Origin with appropriate backup
documentation, (b) mark the customs/shipping documents for the qualifying
component or PRODUCT with the legend: "Copy of blanket NAFTA Certificate of
Origin on file at NORTEL's customs office in Milton, Ontario, Canada." And
(c) mail copies of the NAFTA Certificate of Origin to the other PARTY.

17.16  U.N. Convention on Contracts  The PARTIES agree that the U.N.
Convention on Contracts for the International Sale of Goods (Vienna, 1980)
shall not apply to the MARKETING AGREEMENT nor to any dispute or transaction
arising out of the MARKETING AGREEMENT.

17.17  Dispute Resolution. In the event that a controversy or claim arises
relating to the MARKETING AGREEMENT, or the breach thereof, the PARTIES shall
use good faith efforts to resolve such controversy or claim without resort to
litigation.  Upon written notice of any such dispute ("Dispute Notice"), the
project managers for each PARTY must consult with each other to attempt to
resolve the matter amicably for a period of at least thirty (30) days.  In
the event that the PARTIES are unable to reach an accommodation within such

<PAGE>  30

thirty (30) day period, senior management from both NORTEL and SHIVA with
authority to settle the controversy or claim shall hold a meeting and use
good faith efforts to resolve the dispute within the following thirty (30)
days.  Should the senior management meeting(s) also fail to resolve the
dispute, the PARTIES agree to engage the services of a mutually agreeable
independent mediator prior to resorting to litigation. An attempt to arrive
at a settlement shall be deemed to have failed only if the mediation process
fails to resolve the issue within another thirty (30) day period.

<PAGE>  31

17.18  Taxes.  Prices and fees set forth in the MARKETING AGREEMENT are (a)
exclusive of any applicable excise taxes now existing or hereafter imposed by
any applicable taxing authority; (b) exclusive of the transportation charges
and duty applicable between the shipping location and delivery location; and
(c) inclusive of all other taxes, transportation charges and duty for PRODUCT
which NORTEL purchases from SHIVA or royalty payments NORTEL makes to SHIVA
for which NORTEL is liable shall be separately stated on the invoice from
SHIVA to NORTEL.  Such taxes, transportation charges and duty for royalty
payments SHIVA makes to NORTEL for which SHIVA is liable shall be separately
stated on the invoice from NORTEL to SHIVA.  NORTEL and SHIVA agree not to
assess any applicable excise or sales tax where one PARTY furnishes the other
PARTY a tax exemption certificate, a certificate of authority, a direct pay
permit and/or any equivalent acceptable to the applicable taxing authority.
Either PARTY shall withhold any withholding tax required to be withheld from
payments made to the receiving PARTY pursuant to the MARKETING AGREEMENT. To
assist in obtaining any tax credits for the amounts withheld from payments
made to the receiving PARTY, the paying PARTY shall promptly furnish the
receiving PARTY with such evidence as may be required by the appropriate
taxing authorities to establish that any such tax has been paid.

SHIVA CORPORATION                 NORTHERN TELECOM LIMITED

Signature:                        Signature:
Frank Ingari                      Klaus Buechner
President                         Group Vice President
                                  Multimedia Networks


                                  Signature:
                                  Name:  David Archibald
                                  Title: V.P. and Deputy General
                                         Counsel

<PAGE>  32

                                 EXHIBIT A

                      NORTH AMERICA SERVICE PROVIDERS

TELCOS
                                     Major ISPs and OSP's

AT & T - LD
AT & T - Metro                       UUNet
AT & T - Worldnet                    BBN
AT & T - Interspan                   PSI
AT & T - WICS                        Netcom
BT - MCI - Concert                   AOL
Sprint - LD                          Compuserve
Sprintlink                           Advanced Network Services (ANS)
Sprint - Local                       Erols
WorldCom - LD                        MFS
WorldCom - MFS                       WilTel-WilTech
WorldCom - GridNet International     Digex
WorldCom - Customer Solutions        Mindspring
Frontier
Southwestern Bell                    AAP Caps
Bell Atlantic
Nynex                                GST
Bellsouth                            ELI
PacBell                              Cable and wireless
U.S. West                            Teleport
Ameritech                            US Signal
GTE                                  McCloud Communications
AllTel
Cincinnati Bell
Citizen Telecom
Bell Canada
Unitel
Stentor Companies 
Sasktel
EdTel
NBTel
Alberta Tel
NFTel

<PAGE>  33

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT B

******* ROYALTY PAYMENT **************************** FEATURES

***** shall pay *********************************** for each SHIVA LanRover
Access Switch sold by ***** with a FEATURE described in this Exhibit B.  The
royalty shall be paid by **********************************************
************************************************************ time period of
****************** after *********** of a SHIVA LanRover Access Switch with
any of the features described in this Exhibit B.

FEATURE Descriptions

*******************
***********************************
**************************************************
***************************
**********************
***********************
*************
************************

* These FEATURES are also subject to a *********************************
whereby ************************************** in a LanRover Access Switch
********************************************** of such FEATURE.

<PAGE>  34

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT C

**************** PRODUCT FEATURES

This Exhibit describes PRODUCTS or functionality that shall be ***********
part of the ****** version of a PRODUCT that is ******************* and are
being ****************.  These PRODUCTS or functionality shall not **
************************************** of a PRODUCT that ***********
************************** standard distribution channels.

Rapport 112


*******************

**********************************
********************
*************
*************


OEM Access Port of Rapport ***********

***** developed modifications using ****** developed software and/or hardware,
including but not limited to the following:

*************************

***************************

***************************************

**************************************
************************
***********************************

<PAGE>  35

                                 EXHIBIT D

SHIVA SUPPORT TO NORTEL

Support Requirements

SHIVA shall provide Technical Support seven (7) days a week, twenty four (24)
hours a day.  This support shall be manned during normal business hours 9:00
a.m. - 8:00 p.m. EST.  During all other hours the support shall be on pager
call out.

SHIVA shall provide Manager Technical Support seven (7) days a week, twenty
four (24) hours a day.  This support shall be manned during normal business
hours 9:00 a.m. -8:00 p.m. EST.  During all other hours the technical support
manager shall be on pager call out. 

SHIVA shall provide NORTEL with Training Material and course work for a Train
the Trainer course as required for each new hardware and software general
release.  SHIVA shall provide written updates to these Materials for the time
periods between these general releases.

The PARTIES agree to work together in good faith to determine any remaining
aspects of the detailed support policy that is not covered in this AGREEMENT.

Support Process

Technical support is based on three levels of support, NORTEL shall provide
the first level of support or primary customer interface which is called
NORTEL's Front Line Support (FLS).  NORTEL shall provide second level support
by its Global Technical Support (GTS) group.  NORTEL's GTS group shall be the
interface to SHIVA Technical Support (STS) on all global PRODUCT customer
issues.  Also, designated engineers from NORTEL's Emergency Technical
Assistance Support (ETAS) group shall be able to contact the SHIVA technical
support group for any critical issues.  SHIVA shall provide per mutual
agreement by SHIVA and NORTEL senior management first level support in the
event of failure to achieve fix to E1 error in 24 hours or a Major error
within 30 days. 

SHIVA technical support engineer response time shall be based on the
following:

Normal Business hours: 9am - 8pm EST     One (1) hour response time
Monday to Friday excluding holidays

After hours:  8pm - 9am EST            NORTEL's GTS group may send problem
                                       notification via email or through
                                       SHIVA 'S call tracking system

<PAGE>  36

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

After Hours Emergencies                NORTEL's GTS group shall be provided
                                       with a phone number to use to contact
                                       SHIVA personnel (engineer pager and
                                       manager pager), 15 Minute response
                                       time.

NORTEL's GTS group shall be able to communicate to SHIVA'S STS group via
phone, email, and faxes.

***************************************************************************
**********

Problem definition

Problems shall be defined as follows:

Critical E1             emergency, equipment out of service
E3, Follow-Up           root cause of E1 outage
Major                   Service affecting problem
Minor                   Non-service affecting problem

Service Objective

The following time frames shall be used to specify service objectives for each
type of problem definition.  The time frame is defined from the time that
NORTEL notifies SHIVA Technical support of an escalated issue to the time
that SHIVA provides an acceptable resolution.

Critical E1                            < 24 hours service restored with short
                                       term fix if applicable.  E3 trouble
                                       report opened for long term fix.
E3, Follow-Up                          < 30 days
Major                                  < 30 days
Minor                                  <180 days

* Times from when NORTEL informs SHIVA of a problem.  All E1 and E3 issues
shall be conveyed to SHIVA as soon as reported to NORTEL's GTS group so as to
meet the above time frames.

Escalation of a Problem

NORTEL and SHIVA technical support shall work together to define the
escalation process within each organization and establish the appropriate
interface between the organizations at the necessary level of responsibility.

<PAGE>  37

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

Additional Support or Sustaining Engineering Requirements for Internet Thruway
Application Customers

SHIVA shall use reasonable efforts to implement the Bellcore Software
Introduction Process for all new features developed for Software, including
Bellcore guidelines for MTBF, Test Plans/Results and Release Notes.  NORTEL
and SHIVA shall jointly review test plans/results prior to
implementation/release.

NORTEL must agree, in writing, to any features or functionality that are
removed from Software for a NORTEL customer.

SHIVA agrees to use reasonable efforts to provide the following documentation
to NORTEL for all new PRODUCTS/features:  1. detailed specifications on
PRODUCTS/FEATURES, 2. detailed troubleshooting methods and procedures and 3.
detailed engineering provisions, capacity.

SHIVA and NORTEL support personnel agree to meet within thirty days following
execution of the MARKETING AGREEMENT to define acceptable quality statistics
and develop a quality assurance program.

Support Fees

*****for support for an initial period commencing at the period of execution
of the MARKETING AGREEMENT *********************************************
*****************************************************************************
****************************************************************************
*********************************************************************
****************************************************************************
***************************************************************************
*****************************************************************************
***************************************************************************
****************************************************************************
*****************************************************************************
********************************************************************
*************************************************************************
*************************

SOFTWARE and DOCUMENTATION Maintenance/Releases

SOFTWARE Maintenance

SHIVA shall be responsible for SOFTWARE maintenance of the PRODUCT.  This
includes the release of bug fixes, patches, SOFTWARE updates and maintenance
releases.  Maintenance releases shall include previously agreed upon bug
fixes and patches.  The schedule for SOFTWARE updates shall be mutually
determined by SHIVA and NORTEL.

<PAGE>  38

SHIVA shall support the current major releases (including release revisions)
of SOFTWARE as well as one previous release (including release revisions) of
SOFTWARE in the PRODUCTS.

SHIVA shall provide NORTEL with a list of known bugs in each release of the
PRODUCT SOFTWARE prior to SHIVA's release of such SOFTWARE to NORTEL and upon
identification of any bugs in a release of SOFTWARE previously released to
NORTEL.  SHIVA shall provide all bug fixes (patches) and release notes to
NORTEL's technical support for release to NORTEL's customers.  SHIVA and
NORTEL agree to establish a distribution method for releases.

SOFTWARE Releases/Documentation

All major SOFTWARE releases and upgrades shall be scheduled by SHIVA and
NORTEL in the MTDA. These releases shall contain significant new features and
functionality.  The time frames for upgrades shall be defined by SHIVA and
NORTEL Product management teams.  The release content shall ensure that the
roll-out plans are synchronized between NORTEL and SHIVA product lines.

SHIVA shall provide the standard SHIVA version of documentation for each
release of the SOFTWARE.  Any customization of documentation shall be
negotiated separately.  Documentation includes on-line help, user/reference
guides, release notes and any other applicable documentation.

Knowledge

SHIVA shall provide NORTEL's GTS group access to pertinent existing knowledge
bases for remote access support and product support issues.  Knowledge to
include Frequently Asked Questions (FAQS) and Technical Tips, and Lotus Notes
databases.  It shall also include new tools as developed throughout the life
of the project.  Each of these shall be updated for each release of the
PRODUCTS.  NORTEL technical support shall have access to all public on-line
forums, such as the World Wide Wed site, ftp server, SHIVA BBS and the SHIVA
Fax On Demand server.

NORTEL shall provide SHIVA with access to pertinent knowledge bases related to
frame relay technology.

<PAGE>  39

Hardware Support for SPECIFIC PRODUCT Manufactured and Delivered by SHIVA

The warranty for hardware relating to SPECIFIC PRODUCT that is manufactured
and delivered by SHIVA is specified in Section 11.1.

The following repair service procedures shall be followed by NORTEL technical
support staff for repairs to SPECIFIC PRODUCT(S) that have been manufactured
by SHIVA and supplied to NORTEL:

1)    NORTEL shall call SHIVA to obtain a Return Material Authorization (RMA)
number.

2)    NORTEL shall send the equipment to be repaired to SHIVA as outlined in
the letter of shipping instruction that is included in each order.  All
SPECIFIC PRODUCT(S) to be repaired should be returned in their original or
equivalent packing materials.  The applicable RMA number must be placed on
the address label when the SPECIFIC PRODUCT is shipped to SHIVA.  NORTEL
shall pay for the cost of shipping SPECIFIC PRODUCT to SHIVA.

3)    NORTEL shall call SHIVA to confirm receipt of shipment.

4)    SHIVA shall repair or replace the failed system pursuant to Section 9. 
SHIVA shall pay for the cost of shipping SPECIFIC PRODUCT to NORTEL.

NORTEL is responsible for local sparing of required hardware for their
customers.  SHIVA shall provide recommendations as to the numbers and types
of spares to be stocked.

SHIVA shall provide NORTEL with appropriate statistics regarding hardware
problem tracking.

Manufacturer Discontinuation of SPECIFIC PRODUCT

SHIVA shall support PRODUCT for a period of seven (7) years after
discontinuing manufacture, however, in the event that NORTEL has acquired a
RTM for such PRODUCT, NORTEL shall continue to manufacture such PRODUCT
itself and shall not have the option of requiring that SHIVA continue
manufacture of such PRODUCT.  SHIVA further agrees to notify NORTEL twelve
(12) months prior to discontinuing manufacture of any PRODUCT.  Long term
support fees shall be determined on an annual basis.

<PAGE>  40

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.


                                 EXHIBIT E

SPECIFIC PRODUCT/FEATURE ADDENDUM 1 - Rapport 8

SPECIFIC PRODUCT

Rapport ************************


License Type

******


*******************************

****


Royalties

*********** royalty fee is ********.  The bundled hardware/software SPECIFIC
PRODUCT price includes *******************************************************
*************************************************************************

<PAGE>  41


CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.


SPECIFIC PRODUCT/FEATURE ADDENDUM 2 - Rapport 112 **********************

SPECIFIC PRODUCT

LanRover Access Switch ********************** Rapport 112)


License Type

******





Royalties

*********** royalty fee is ********.  The bundled hardware/software SPECIFIC
PRODUCT price includes ****************************************************
***************************************************************************.

<PAGE>  42


CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.


SPECIFIC PRODUCT/FEATURE ADDENDUM 3 - Rapport 112 ************************

SPECIFIC PRODUCT

Rapport 112 ************************


License Type

******


Marketing Provisions

**********************.  In accordance with Section 4.4 of the MARKETING
AGREEMENT, NORTEL may sell and distribute Rapport 112 it ************ (i)
into the CARRIER/ISP MARKET and (ii) internally for NORTEL's own use.

****************** Provision.  The following ****************** provisions
shall apply to the Rapport 112 and all derivatives thereof which result from
the development activities contemplated under the MARKETING AGREEMENT or the
MTDA.  The PARTIES agree to the following ************************
************ rights for the term commencing upon the EFFECTIVE DATE of the
MARKETING AGREEMENT and continuing unless *********** is revoked pursuant to
the provisions of Section 5.1 and 5.2 of the MARKETING AGREEMENT.  SHIVA
shall ******************************* the Rapport 112 or SHIVA's version of
the Rapport 112 (SHIVA LanRover Access Switch), and evolutions and
derivatives thereof, within the ******************************************. 
In addition, SHIVA shall ************** future agreements with distribution
partners (including but not limited to Other Equipment Manufacturers) other
than NORTEL, that shall permit such distribution partners to *******
********************************* Rapport 112 (SHIVA LanRover Access Switch)
or any product that is similar to the LanRover Access Switch and evolutions
or derivatives thereof, into the ******************************************. 
Not including existing CUSTOMER obligations, and for home office application,
until such time as the SHIVA ******************************* is available and
functionally equivalent to THIRD PARTY products in the market, NORTEL shall
***************************************************************************
***************************************************************.  Such
*********** provision shall not hinder NORTEL's right to complement SHIVA
technology with other technologies and/or products to meet CUSTOMER
requirements in the event SHIVA technology cannot meet such customer
requirement.  

In the event that NORTEL sells or distributes ********************************
**************************************************************************

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

********* then such activity shall not constitute a breach of the MARKETING
AGREEMENT but may, ****************************************************
***************************.  Notwithstanding the foregoing, in the event
that a CUSTOMER insists that NORTEL support products other than Rapport 112
in their network environment due to feature/functionality requirements or to
integrate with existing installed base technology, despite NORTEL's
commercially reasonable effort to position and promote the advantage of the
NORTEL/SHIVA technology and value to the CUSTOMER, and **********************
*********************************************************************
*******************************************************************
**************************************************************************
***********************.  However, in such event SHIVA shall be able to sell
the SHIVA LanRover Access Switch *************************.  NORTEL support of
products other than Rapport 112 in this instance shall mean *************
***************************************************************.  It shall
exclude the following NORTEL activities:  *******************************
***************************************************************************
*************************.  Further, NORTEL shall not ********************
************************************************************************
************************************************************************. 
This limitation shall not apply to development activities that NORTEL
undertakes for a specific account.  This limitation shall not apply to
development activities that NORTEL undertakes pursuant to a contract with the
first CUSTOMER requesting such services.  With respect to any subsequent
CUSTOMERS for such services, NORTEL may, at its option, either (i) cause new
software to be developed independently of the activities carried out for
another CUSTOMER or (ii) re-use the previously developed software upon
payment to SHIVA of ***************************** for the sale at issue, up
to a maximum of ********************************************************. 
The number of ports used for the calculation of this payment to SHIVA shall
be ***************************************************************.  NORTEL
shall also ********************************************************
**************************************************************************. 
NORTEL agrees to actively promote the SHIVA/NORTEL solution and to
acknowledge SHIVA's contribution to the ****************.


In the event ****************** has been terminated, each PARTY shall be able
to ********** the Rapport 112 or, in the case of SHIVA, the LanRover Access
Switch and, in the case of NORTEL, **************************************
***********************************************************************
*********.

Royalties

NORTEL agrees to pay SHIVA a royalty rate of ****************************
*********** for the Rapport 112.  ************************ NORTEL has
incurred a payment obligation, *******************************************
***********************************************************************

<PAGE>  44


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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.


***********************************************************************
********************************************* of Rapport 112 ***************
*************************************.

In 1997, and prior to any notification of revocation of the exclusivity
provisions, NORTEL shall make ************************ payments *******
****************************************************************************
***************************************************************************
****************************************************************************. 
Invoices for these royalties shall be issued upon receipt of the royalty
report described in Exhibit H.  ***************************************
***************************************.  In the event that the ******
*********** provisions are canceled as provided in the section entitled
Marketing Provisions, above, NORTEL shall *********************************
**********************************.

At the end of 1997, any advance royalties paid by NORTEL to SHIVA which exceed
the royalties earned by SHIVA based on the royalty calculation set forth in
Exhibit H shall be ************************ royalties resulting from ******
************.  These unused royalties *************************************
***************************************************************************
*********************.  In the event of notification that the ***********
********* is terminated there shall be *********************************
********.  In the event that the total royalties due exceed the ****
****************** the difference shall be calculated within ****************
*****************************************************************************
*****************.

The equivalent of **********************************************************
shall be ********************************************************************
********************************* royalty payment described above) provided
the *****************************************************************
NORTEL's Rapport 112 *************************************************
*****************************************************************************
****************************************************************************
***************************************************.  By way of example, *
***************************************************************************
***************************************************************************
*******************************************************************
*************** assumes the following:  *******************************
*************************** Rapport 112 **********************************
*******************************************************************
CARRIER/ISP MARKET ****************************************************
************************************.

However, for the purposes of NORTEL sales for which **************************
**********************************************************************
*******************************.

**********************.  In the event NORTEL sells and distribute Rapport 112
**************************** Carrier/ISP Market **********************

<PAGE>  45


CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

****************, NORTEL shall pay royalties as provided for sales of Rapport
112 **********************************************************************
********************************************

<PAGE>  46


CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

SPECIFIC PRODUCT/FEATURE ADDENDUM 4 - Rapport **** Access Router

SPECIFIC PRODUCT

Rapport **** Access Router


License Type

******


Modifications to License Type *

*****


Royalties

****** shall pay ***** a royalty of ************************************
***************************************************************************
**********************************************************************
*************************************************************************
**************************************************  In each case, ******
*************************************************************************
************************************************************************
****************************************************************************
*************************************************************************
***************************************************************************
**********************************************************************
***********************************************************************
*****************************************************************************
***************************************************************************
********************************************************.

Royalties for ******************************** shall be calculated **********
***************************************************************************
**************************************************************************
**************************************************************************
*****************************************.

<PAGE>  47


CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

SPECIFIC PRODUCT/FEATURE ADDENDUM 5 - Exhibit C for Rapport 112 and Rapport
***********

SPECIFIC FEATURES

************************* as described in Exhibit C for Rapport 112 and
Rapport ***********.


License Type

******


Modifications to License Type *

*****


Royalties

*****

<PAGE>  48


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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT F


***** R&D Deliverable Dependencies

************** to be delivered on or before *******************************
*************************.

***************************** to be delivered on or before 
************************************************************************.

************ to be delivered on or before **********************************
******************.

****************** to be delivered on or before *****************************
*****************************.

************* to be delivered on or before the *******************************
******************.

*********************************** to be delivered on or before *************
***************************************************************.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.


                                 EXHIBIT G

The MINIMUM MARKET PERFORMANCE OBJECTIVE is ******** achievement of **********
***************************************************************************
*************************************************************************
************************************************************.  This metric
may only be amended by mutual agreement of the PARTIES, in writing.

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT H


Rapport 112:  *************** Computation 

***** shall be paid royalties at a rate of ******************************
************* Rapport 112 product ************************************.  Such
royalty payment shall be applied toward *************************** royalty
payments described in SPECIFIC PRODUCT/FEATURE ADDENDUM 3 of Exhibit E of the
MARKETING AGREEMENT.

**************************** Rapport 112 Product *************

********************, NORTEL shall summarize ***************************
Rapport 112 units **************************************, defined as *******
***********************************************************************
*************************************************************************
**************************************** royalty due to ******************
*************************** shall be ******************************.

**************** (Rapport 112 Product ***********************************
*********

Rapport 112 product ********************************************************
******************************************************************, shall be
subject to a  royalty based on the following formula:

************************************************************************
royalty ********

************************************* royalty ********************* Royalty

******* royalty

************** royalty ******** shall be a ******************************
***************************************.

Royalties shall be adjusted ********* as required to reflect ***************
********************.

Payment Schedule

Royalties shall be calculated **********************************************
************************ shall be sent ***********************************
******************.

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CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

****** shall maintain complete and accurate records of all royalty
calculations.  Such records shall be maintained in accordance with generally
accepted accounting principles.  ****** shall retain such records for the
************************************************************************* may
request an audit of royalty calculation records by an independent auditor
reasonably acceptable to ******.  During the period in which ****** is
required to maintain royalty calculation records, such auditors shall have
reasonable access to such records at a mutually agreeable time and location
for the purposes of conducting an audit.  ***** shall bear all audit expenses
unless such audit reveals that ****** has understated royalties by more than
****************** in which such case ****** shall pay all reasonable costs
associated with the audit.  Prompt adjustment shall be made to compensate for
any understatement revealed by the audit.

<PAGE>  52


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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT I

SERVICE PROVIDER GROUP

SPG is a group of ***** provided employees funded by ****** and assigned to
exclusively support ****** to promote the Rapport PRODUCT business. The
primary purposes of this group is to provide pre-sales and post-sales support
of the Rapport PRODUCT in the CARRIER/ISP MARKET.

***** employees staffing the SPG shall continue to be paid by ***** but shall
be assigned ************************** of the time to ****** related
activities unless otherwise agreed to by ****** in writing.

Before assigning an individual to SPG, whether as an initial assignment or a
subsequent assignment, ***** shall (i) notify ****** of the proposed
assignment, (ii) shall introduce the individual to appropriate ******
representatives (and, upon request, provide such representatives with the
opportunity to interview the individual) and (iii) shall provide ****** with
a resume and other information about the individual reasonably requested by
******.  If ****** in good faith objects to the proposed assignment, the
PARTIES shall attempt to resolve ******** concerns on a mutually agreeable
basis.  If the PARTIES have not been able to resolve ******** concerns within
***************************** shall not assign the individual to that
position and shall propose to ****** the assignment of another individual of
suitable ability and qualifications.  Personnel filling SPG positions may not
be transferred or reassigned until a suitable replacement has been approved
by ******.

***** and the SPG employees shall execute non-disclosure agreements and non-
circumvention agreements in a form acceptable to ******, prior to gaining
access to any CONFIDENTIAL INFORMATION.  The non-disclosure, non-circumvention
agreement shall contain a restriction that neither ***** nor its employees (in
particular SPG employees) shall solicit any CUSTOMERS that were solicited for
the benefit of ******* during the term of the MARKETING AGREEMENT and that the
period of this restriction shall be for term of this MARKETING AGREEMENT or,
in the case of ***** employees (in particular SPG employees), for the period
of their employment by *****.

The personnel to staff SPG shall be approved within ************* of the
EFFECTIVE DATE.

***** agrees that, with respect to the planned departure of any individual
serving on SPG, ***** shall use commercially reasonable efforts to initiate
the procedures set forth below within a sufficient amount of time in advance
of the planned departure date to allow the PARTIES to agree upon a replacement
individual and for such individual to be permanently assigned and fully
trained on-site in the responsibilities he or she shall be assuming prior to
the predecessor's departure.

<PAGE>  53

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

In the case of an unplanned departure of an individual holding a SPG position,
***** shall promptly, and in no event longer than **************** from the
day of the predecessor's departure, name and have accepted a replacement for
the open SPG position who is properly educated, trained and fully qualified
for the SPG services such replacement is to perform.  With ******** prior
written approval, ***** may use a temporary replacement to fill a SPG position
until the permanent replacement is available.  In the event that *****
provides a temporary replacement, that person's time at ****** shall be
scheduled so as to overlap with the permanent replacement's arrival by at
least **************************.

Notwithstanding any provision to the contrary, nothing contained in Article 12
or this Exhibit I shall be deemed or construed to in any way limit *******
ability to terminate any of its employees for cause.

Qualifications, Retention and Replacement of SPG Personnel.

***** shall assign the number of SPG personnel specified in Section 12.2 of
the MARKETING AGREEMENT.  The personnel ***** assigns to perform the SPG
responsibilities shall be properly educated, trained and fully qualified for
the services they are to perform.

NORTEL and SHIVA both agree that it is in their best interests to keep the
turnover rate of the ***** personnel performing the SPG responsibilities to a
reasonably low level.  Accordingly, if ****** believes that ******* turnover
rate may be excessive and so notifies ************ shall provide data
concerning its turnover rate, meet with ****** to discuss the reasons for,
and impact of, the turnover rate and otherwise use its best efforts to keep
such turnover rate to a reasonably low level.  If appropriate, ***** shall
submit to ****** its proposal for reducing the turnover rate, and the PARTIES
shall mutually agree to a program to bring the turnover rate down to an
acceptable level.  In any event, notwithstanding transfer or turnover of
personnel, ***** remains obligated to perform the SPG responsibilities
without degradation and in accordance with the AGREEMENT.

In the event that ****** determines in good faith that the continued
assignment to the ****** account of one of the ***** personnel is not in the
best interests of ******, then ****** shall give ***** written notice to that
effect.  Promptly after receipt of such notice, ***** shall investigate the
matters stated in such notice, discuss its findings with ****** and resolve
any problems with such person.  If, following such period, ****** requests
replacement of such person, ***** shall replace that person with another
person of suitable ability and qualifications as expeditiously as possible.

Objective

The SPG members shall be assigned to specific ****** market regions to work
with ******** sales and marketing organizations.  The specific number of SPG

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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

resources shall be agreed to based on a ************* rolling forecast, and
be committed to in the prior quarter by the ************ management
committee.  ***** is responsible for the assignment and recruitment of
skilled and trained individuals, 

Mode of Operation

While the SPG shall remain under the management and administration of *****
***********, the day-to-day activities shall be at the direction of the
regional ****** management.  All customer sales and contracts shall be
subject to normal ****** policies.  The following areas highlight some of the
specific interfaces and policies:

Account management - Remain as sole responsibility of ****** sales
   organization,
Sales proposal - Subject to normal ********** corporate policies
Non-standard commitments - Future product commitments not contained in an
   approved NORTEL-SHIVA plan of record (POR) must be reviewed and
   approved by ****** Rapport product management and ***** engineering.
Price and quotation - subject to regional marketing guidelines; non-standard
   pricing subject to ****** Rapport core marketing approval.
Contracts - ****** responsibility and subject to ****** legal reviews.
Post sales support - Same as regional ****** CUSTOMER services policies.
Trial support - ************ responsibility.

Sales Interface Chain

Customer to ****** account Manager to ****** + SPG Sales Support to ******
********************

Customer Support Interface Chain

Customer to ****** Customer Services (FLS *) to ******************** to *****
Engineering

*FLS = regional first line support and global first line support organization

SPG Resources

Pre-sales Support: 
Business development managers to supplement ****** account managers in
   strategy development
Sales engineering specialists to complement ****** Rapport sales engineers to
   provide technical sales support, proposals, customer demo support and
   engineering

<PAGE>  55


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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

Post-sales Support:
Network consultants to complement ****** Rapport network consultants for
   technical network deployment issues and support.
Solution test engineers to complement ****** FLS/GTS in trial support and
   CUSTOMER configuration engineering and test.

In addition, a small group of centrally located technical/product experts
shall be working with ****** Product Line Management (PLM) and lead customers
in new feature definition and in ensuring that ****************************
******** are managed within ***** engineering.

The SPG staff is not to be used to replace ******* commitment for product
quality/QA, customer services and standard vendor support functions.



Resource requirements (1Q/2Q) - excluding administration support

Function *************************************************************
***************************************************************
Business development
managers*************************************************************
Sales engineering 
specialists**********************************************************
Network consultants**************************************************
Solution test engineers**********************************************
Product Experts/Project
Managers*************************************************************
Total by Region******************************************************

SPG Cost:

****** costs to be charged including ************* plus *******************
********** including ****************************** and ******** and
**********.  In the event that SPG is located within ****** facilities, the
***** charge would be **********************.

For planning purposes, it is assumed that SPG cost is budgeted at ***********
****************************************************************.

<PAGE>  56


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EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

Assumption:

***** shall assign a ****** account manager for issues of total relationship
  and therefore not be funded directly by ******.
Product Marketing support for ENTERPRISES shall continue to be provided
  through ******* Marketing organization as SPG is focused on ************.
As SPG is dedicated to provide ****** with the services described in this
  Exhibit I, the ***** regional account management organizations shall be
  encouraged to support******* in the region.

<PAGE>  57

                                 EXHIBIT J

SHIVA's THIRD PARTY Competitors

Access Beyond
Cascade
Cisco 
Bay Networks/Xylogics
Ascend 
3Com/USR
Livingston
Microcom

<PAGE>  58

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION.  ASTERISKS DENOTE SUCH OMISSIONS.

                                 EXHIBIT K

******** THIRD PARTY Competitors

********
*******
***************************
******************
****************************
******************
***********************************
*******************************
************************
**********


<PAGE>  59