Exhibit 10.13

December 18, 1997

Bob Cirrone
9 Trenton Street
Melrose, Massachusetts 02176

Dear Bob:

On behalf of Shiva Corporation, I am pleased to offer you the
position of Senior Vice President, Chief Financial Officer,
reporting directly to me.

Your initial base compensation will be $7884.61 bi-weekly, which
is $205,000 annualized.  Your recurring compensation will
include a base salary and a 50% annualized bonus paid out
quarterly based on the company meeting its operating plan and
other objectives set between us and with the Board of Directors.

Under the terms of the Shiva Corporation 1988 or 1997 Stock
Option Plans, stock option grants are subject to approval and
grant by the Compensation Committee of the Board of Directors.
Shiva Corporation management will recommend to the Compensation
Committee that you be granted an initial stock grant in the
amount of 275,000 shares at the time of the next Compensation
Committee meeting after your start date or via written consent in
lieu of such meeting, according to the then current standard
stock option terms and conditions. Your initial vesting schedule
is as follows:

     68,750 (25%) will vest immediately upon date of grant
     17,187.5 (6.25%) will vest 15 months after date of grant, and
     17,187.5  (6.25%) will continue to vest quarterly for the
     remaining eleven quarters thereafter.

In the event of a change of control of Shiva within one year of
your start date, 50% of your outstanding options will vest
immediately.  In the event of a change of control of Shiva after
one year of your start date, 100% of your outstanding stock
options will vest immediately.

You are entitled to participate immediately upon your start date
in our benefit programs.  Shiva expects that you will be pleased
with the company's medical and disability programs.  Reasonable
relocation and family visit expenses will be provided.

December 18, 1997
Page 2

In the event of your involuntary termination other than for
cause, you will be eligible to receive severance pay of one
year's base salary.

This offer is contingent upon your compliance with the
Immigration Reform and Control Act.  In addition, enclosed is a
Non-Disclosure Agreement and I-9 Form for your review that all
Shiva employees are required to sign.

We look forward to your joining Shiva.  If you have any
questions, please do not hesitate to call me at (781) 687-1890.

Sincerely,
 

James Zucco
President & CEO


Acceptance: /s/ R.P. Cirrone           Date: 12/22/97
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