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                                SYNC RESEARCH, INC.

                        1996 NON-EXECUTIVE STOCK OPTION PLAN

                              AMENDED: AUGUST 21, 1998

     1.   PURPOSES OF THE PLAN.  The purposes of this Stock Option Plan are
to attract and retain the best available personnel for positions of substantial
responsibility, to provide additional incentive to the Employees and Consultants
of the Company and to promote the success of the Company's business.  Options
granted hereunder shall be Nonstatutory Stock Options.

     2.   DEFINITIONS.  As used herein, the following definitions shall apply:

          (a)  "ADMINISTRATOR" shall mean the Board or any of its Committees
appointed pursuant to Section 4 of the Plan.

          (b)  "AFFILIATE" shall mean an entity other than a Subsidiary (as
defined below) in which the Company owns an equity interest.

          (c)  "APPLICABLE LAWS" shall have the meaning set forth in Section
4(a) below.

          (d)  "BOARD" shall mean the Board of Directors of the Company.

          (e)  "CODE" shall mean the Internal Revenue Code of 1986, as amended.

          (f)  "COMMITTEE" shall mean the Committee appointed by the Board of
Directors in accordance with Section 4(a) of the Plan, if one is appointed.

          (g)  "COMMON STOCK" shall mean the Common Stock of the Company.

          (h)  "COMPANY" shall mean Sync Research, Inc., a Delaware corporation.

          (i)  "CONSULTANT" means any person, including an advisor, who is
engaged by the Company or any Parent or Subsidiary to render services and is
compensated for such services, provided that the term Consultant shall not
include Directors or Officers.

          (j)  "CONTINUOUS STATUS AS AN EMPLOYEE OR CONSULTANT" shall mean the
absence of any interruption or termination of service as an Employee or
Consultant.  Continuous Status as an Employee or Consultant shall not be
considered interrupted in the case of sick leave, military leave, or any other
leave of absence approved by the Administrator; PROVIDED that such leave is for
a period of not more than 90 days or reemployment upon the expiration of such
leave is guaranteed by contract or statute.  For purposes of this Plan, a change
in status from an Employee to a Consultant or from a Consultant to an Employee
will not constitute a termination of employment.

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          (k)  "DIRECTOR" shall mean a member of the Board.

          (l)  "EMPLOYEE" shall mean any person (excluding any Officer or
Director) employed by the Company or any Parent, Subsidiary or Affiliate of the
Company.  Notwithstanding the foregoing, an Officer who was not previously
employed by the Company and for whom an Option grant is an inducement essential
to the Officer's entering into an employment relationship or contract with the
Company shall be treated as an Employee for purposes of the Option grant made to
the Officer in connection with commencement of the Officer's employment with the
Company.

          (m)  "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934, as
amended.

          (n)  "FAIR MARKET VALUE" means, as of any date, the value of Common
Stock determined as follows:

               (i)    If the Common Stock is listed on any established stock
exchange or a national market system including without limitation the National
Market of the National Association of Securities Dealers, Inc. Automated
Quotation ("Nasdaq") System, its Fair Market Value shall be the closing sales
price for such stock as quoted on such system on the date of determination (if
for a given day no sales were reported, the closing bid on that day shall be
used), as such price is reported in The Wall Street Journal or such other source
as the Administrator deems reliable;

               (ii)   If the Common Stock is quoted on the Nasdaq System (but
not on the National Market thereof) or regularly quoted by a recognized
securities dealer but selling prices are not reported, its Fair Market Value
shall be the mean between the bid and asked prices for the Common Stock or;

               (iii)  In the absence of an established market for the Common
Stock, the Fair Market Value thereof shall be determined in good faith by the
Administrator.

          (o)  "NONSTATUTORY STOCK OPTION" shall mean an Option not intended to
qualify as an Incentive Stock Option, as designated in the applicable written
option agreement.

          (p)  "OFFICER" shall mean a person who is appointed or elected by the
Board of Directors as an officer of the Company, including but not limited to a
person who is an officer of the Company within the meaning of Section 16 of the
Exchange Act and the rules and regulations promulgated thereunder.

          (q)  "OPTION" shall mean a stock option granted pursuant to the Plan.

          (r)  "OPTIONED STOCK" shall mean the Common Stock subject to an
Option.

          (s)  "OPTIONEE" shall mean an Employee or Consultant who receives an
Option.

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          (t)  "PARENT" shall mean a "parent corporation," whether now or
hereafter existing, as defined in Section 424(e) of the Code.

          (u)  "PLAN" shall mean this 1996 Non-Executive Stock Option Plan.

          (v)  "RULE 16b-3" shall mean Rule 16b-3 promulgated under the Exchange
Act as the same may be amended from time to time, or any successor provision.

          (w)  "SHARE" shall mean a share of the Common Stock, as adjusted in
accordance with Section 14 of the Plan.

          (x)  "SUBSIDIARY" shall mean a "subsidiary corporation," whether now
or hereafter existing, as defined in Section 424(f) of the Code.

     3.   STOCK SUBJECT TO THE PLAN.  Subject to the provisions of Section 14 of
the Plan, the maximum aggregate number of shares that may be optioned and sold
under the Plan is 2,107,758 shares of Common Stock.  The Shares may be
authorized, but unissued, or reacquired Common Stock.

     If an Option should expire or become unexercisable for any reason without
having been exercised in full, the unpurchased Shares that were subject thereto
shall, unless the Plan shall have been terminated, become available for future
grant under the Plan.  Notwithstanding any other provision of the Plan, shares
issued under the Plan and later repurchased by the Company shall not become
available for future grant under the Plan.

     4.   ADMINISTRATION OF THE PLAN.

          (a)  COMPOSITION OF ADMINISTRATOR.  With respect to grants of Options
to Employees or Consultants, the Plan shall be administered by (A) the Board or
(B) a Committee designated by the Board, which Committee shall be constituted in
such a manner as to satisfy the Applicable Laws.  If a Committee has been
appointed pursuant to this Section 4(a), such Committee shall continue to serve
in its designated capacity until otherwise directed by the Board.  From time to
time the Board may increase the size of any Committee and appoint additional
members thereof, remove members (with or without cause) and appoint new members
in substitution therefor, fill vacancies (however caused) and remove all members
of a Committee and thereafter directly administer the Plan, all to the extent
permitted by the Applicable Laws.

          (b)  POWERS OF THE ADMINISTRATOR.  Subject to the provisions of the
Plan and in the case of a Committee, the specific duties delegated by the Board
to such Committee, the Administrator shall have the authority, in its
discretion:

               (i)    to determine the Fair Market Value of the Common Stock,
in accordance with Section 2(m) of the Plan;

               (ii)   to select the Employees and Consultants to whom Options
may from time to time be granted hereunder;

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               (iii)  to determine whether and to what extent Options are
granted hereunder;

               (iv)   to determine the number of shares of Common Stock to be
covered by each such award granted hereunder;

               (v)    to approve forms of agreement for use under the Plan;

               (vi)   to determine the terms and conditions, not inconsistent
with the terms of the Plan, of any award granted hereunder (including, but not
limited to, the share price and any restriction or limitation, or any vesting
acceleration or waiver of forfeiture restrictions regarding any Option and/or
the shares of Common Stock relating thereto, based in each case on such factors
as the Administrator shall determine, in its sole discretion);

               (vii)  to reduce the exercise price of any Option to the then
current Fair Market Value if the Fair Market Value of the Common Stock covered
by such Option shall have declined since the date the Option was granted.

          (c)  EFFECT OF ADMINISTRATOR'S DECISION.  All decisions,
determinations and interpretations of the Administrator shall be final and
binding on all Optionees and any other holders of any Options.

     5.   ELIGIBILITY.

          (a)  RECIPIENTS OF GRANTS.  Nonstatutory Stock Options may be granted
to Employees and Consultants.  An Employee or Consultant who has been granted an
Option may, if he or she is otherwise eligible, be granted an additional Option
or Options.

          (b)  TYPE OF OPTION.  Each Option shall be designated in the written
option agreement as a Nonstatutory Stock Option.

          (c)  NO EMPLOYMENT RIGHTS.  The Plan shall not confer upon any
Optionee any right with respect to continuation of employment or consulting
relationship with the Company, nor shall it interfere in any way with his or her
right or the Company's right to terminate his or her employment or consulting
relationship at any time, with or without cause.

     6.   TERM OF PLAN.  The Plan shall become effective upon the earlier to
occur of its adoption by the Board or its approval by the stockholders of the
Company as described in Section 20 of the Plan.  It shall continue in effect for
a term of ten (10) years unless sooner terminated under Section 16 of the Plan.

     7.   TERM OF OPTION.  The term of each Option shall be the term stated in
the Option Agreement.  However, in the case of an Option granted to an Optionee
who, at the time the Option is granted, owns stock representing more than ten
percent (10%) of the voting power of all classes of stock of the Company or any
Parent or Subsidiary, the term of the Option shall be 

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five (5) years from the date of grant thereof or such shorter term as may be 
provided in the Option Agreement.

     8.   LIMITATION ON GRANTS TO EMPLOYEES.  Subject to adjustment as provided
in this Plan, the maximum number of Shares which may be subject to options
granted to any one Employee under this Plan for any fiscal year of the Company
shall be 500,000.

     9.   OPTION EXERCISE PRICE AND CONSIDERATION.

          (a)  EXERCISE PRICE.  The per Share exercise price for the Shares to
be issued pursuant to exercise of an Option shall be such price as is determined
by the Administrator, provided, however, that the per Share exercise price shall
be no less than 85% of the Fair Market Value per Share on the date of grant.
Notwithstanding anything to the contrary in the immediately preceding sentence,
in the case of an Option granted on or after the effective date of registration
of any class of equity security of the Company pursuant to Section 12 of the
Exchange Act and prior to six months after the termination of such registration,
the per Share exercise price shall be no less than 100% of the Fair Market Value
per Share on the date of grant.

          (b)  PERMISSIBLE CONSIDERATION.  The consideration to be paid for the
Shares to be issued upon exercise of an Option, including the method of payment,
shall be determined by the Administrator and may consist entirely of (1) cash,
(2) check, (3) other Shares that (x) in the case of Shares acquired upon
exercise of an Option either have been owned by the Optionee for more than six
months on the date of surrender or were not acquired, directly or indirectly,
from the Company, and (y) have a Fair Market Value on the date of surrender
equal to the aggregate exercise price of the Shares as to which said Option
shall be exercised, (4) authorization from the Company to retain from the total
number of Shares as to which the Option is exercised that number of Shares
having a Fair Market Value on the date of exercise equal to the exercise price
for the total number of Shares as to which the Option is exercised, (5) delivery
of a properly executed exercise notice together with irrevocable instructions to
a broker to deliver promptly to the Company the amount of sale or loan proceeds
required to pay the exercise price, (7) a combination of any of the foregoing
methods of payment, (8) a combination of any of the foregoing methods of payment
at least equal in value to the stated capital represented by the Shares to be
issued, plus a promissory note for the balance of the exercise price, or
(9) such other consideration and method of payment for the issuance of Shares to
the extent permitted under Applicable Laws.  In making its determination as to
the type of consideration to accept, the Administrator shall consider if
acceptance of such consideration may be reasonably expected to benefit the
Company.

     10.  EXERCISE OF OPTION.

          (a)  PROCEDURE FOR EXERCISE; RIGHTS AS A STOCKHOLDER.  Any Option
granted hereunder shall be exercisable at such times and under such conditions
as determined by the Administrator, including performance criteria with respect
to the Company and/or the Optionee, and as shall be permissible under the terms
of the Plan.

          An Option may not be exercised for a fraction of a Share.

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          An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company.  Full payment may, as authorized by the Administrator, consist of any
consideration and method of payment allowable under Section 9(b) of the Plan.
Until the issuance (as evidenced by the appropriate entry on the books of the
Company or of a duly authorized transfer agent of the Company) of the stock
certificate evidencing such Shares, no right to vote or receive dividends or any
other rights as a stockholder shall exist with respect to the Optioned Stock,
notwithstanding the exercise of the Option.  The Company shall issue (or cause
to be issued) such stock certificate promptly upon exercise of the Option.  No
adjustment will be made for a dividend or other right for which the record date
is prior to the date the stock certificate is issued, except as provided in
Section 14 of the Plan.

          Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be available, both for purposes of the
Plan and for sale under the Option, by the number of Shares as to which the
Option is exercised.

          (b)  TERMINATION OF STATUS AS AN EMPLOYEE OR CONSULTANT.  In the event
of termination of an Optionee's Continuous Status as an Employee or Consultant,
such Optionee may, but only within thirty (30) days or such other period of
time, not exceeding six (6) months in the case of a Nonstatutory Stock Option,
as is determined by the Administrator, after the date of such termination (but
in no event later than the date of expiration of the term of such Option as set
forth in the Option Agreement), exercise his or her Option to the extent that he
or she was entitled to exercise it at the date of such termination.  To the
extent that the Optionee was not entitled to exercise the Option at the date of
such termination, or if the Optionee does not exercise such Option (which he or
she was entitled to exercise) within the time specified herein, the Option shall
terminate.

          (c)  DISABILITY OF OPTIONEE.  Notwithstanding Section 10(b) above, in
the event of termination of an Optionee's Continuous Status as an Employee or
Consultant as a result of his or her total and permanent disability (as defined
in Section 22(e)(3) of the Code), he or she may, but only within six (6) months
(or such other period of time not exceeding twelve (12) months as is determined
by the Administrator, from the date of such termination (but in no event later
than the date of expiration of the term of such Option as set forth in the
Option Agreement), exercise his or her Option to the extent he or she was
entitled to exercise it at the date of such termination.  To the extent that he
or she was not entitled to exercise the Option at the date of termination, or if
he does not exercise such Option (which he was entitled to exercise) within the
time specified herein, the Option shall terminate.

          (d)  DEATH OF OPTIONEE.  In the event of the death of an Optionee:

               (i)    during the term of the Option who is at the time of his
death an Employee or Consultant of the Company and who shall have been in
Continuous Status as an Employee or Consultant since the date of grant of the
Option, the Option may be exercised, at any time within six (6) months (or such
other period of time, not exceeding twelve (12) months, 

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as is determined by the Administrator) following the date of death (but in no 
event later than the date of expiration of the term of such Option as set 
forth in the Option Agreement), by the Optionee's estate or by a person who 
acquired the right to exercise the Option by bequest or inheritance but only 
to the extent of the right to exercise that would have accrued had the 
Optionee continued living and remained in Continuous Status as an Employee or 
Consultant three (3) months (or such other period of time as is determined by 
the Administrator as provided above) after the date of death, subject to the 
limitation set forth in Section 5(b); or

               (ii)   within thirty (30) days (or such other period of time not
exceeding three (3) months as is determined by the Administrator) after the
termination of Continuous Status as an Employee or Consultant, the Option may be
exercised, at any time within six (6) months following the date of death (but in
no event later than the date of expiration of the term of such Option as set
forth in the Option Agreement), by the Optionee's estate or by a person who
acquired the right to exercise the Option by bequest or inheritance, but only to
the extent of the right to exercise that had accrued at the date of termination.

          (e)  EXTENSION OF EXERCISE PERIOD.  The Administrator shall have full
power and authority to extend the period of time for which the Option is to
remain exercisable following termination of an Optionee's Continuous Status as
an Employee or Consultant from the periods set forth in Sections 10(b), 10(c)
and 10(d) above or in the Option Agreement to such greater time as the Board
shall deem appropriate, provided that in no event shall such option be
exercisable later than the date of expiration of the term of such Option as set
forth in the Option Agreement."

     11.  WITHHOLDING TAXES.  As a condition to the exercise of Options granted
hereunder, the Optionee shall make such arrangements as the Administrator may
require for the satisfaction of any federal, state, local or foreign withholding
tax obligations that may arise in connection with the exercise, receipt or
vesting of such Option.  The Company shall not be required to issue any Shares
under the Plan until such obligations are satisfied.

     12.  STOCK WITHHOLDING TO SATISFY WITHHOLDING TAX OBLIGATIONS.  At the
discretion of the Administrator, Optionees may satisfy withholding obligations
as provided in this paragraph.  When an Optionee incurs tax liability in
connection with an Option which tax liability is subject to tax withholding
under applicable tax laws, and the Optionee is obligated to pay the Company an
amount required to be withheld under applicable tax laws, the Optionee may
satisfy the withholding tax obligation by one or some combination of the
following methods:  (a) by cash payment, or (b) out of Optionee's current
compensation, or (c) if permitted by the Administrator, in its discretion, by
surrendering to the Company Shares that (i) in the case of Shares previously
acquired from the Company, have been owned by the Optionee for more than six
months on the date of surrender, and (ii) have a fair market value on the date
of surrender equal to or less than Optionee's marginal tax rate times the
ordinary income recognized, or (d) by electing to have the Company withhold from
the Shares to be issued upon exercise of the Option that number of Shares having
a fair market value equal to the amount required to be withheld.  For this
purpose, the fair market value of the Shares to be withheld shall 

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be determined on the date that the amount of tax to be withheld is to be 
determined (the "TAX DATE").

          All elections by an Optionee to have Shares withheld to satisfy tax
withholding obligations shall be made in writing in a form acceptable to the
Administrator and shall be subject to the following restrictions:

          (a)  the election must be made on or prior to the applicable Tax Date;

          (b)  once made, the election shall be irrevocable as to the particular
Shares of the Option as to which the election is made; and

          (c)  all elections shall be subject to the consent or disapproval of
the Administrator.

          In the event the election to have Shares withheld is made by an
Optionee and the Tax Date is deferred under Section 83 of the Code because no
election is filed under Section 83(b) of the Code, the Optionee shall receive
the full number of Shares with respect to which the Option is exercised but such
Optionee shall be unconditionally obligated to tender back to the Company the
proper number of Shares on the Tax Date.

     13.  NON-TRANSFERABILITY OF OPTIONS.  The Option may not be sold, pledged,
assigned, hypothecated, transferred, or disposed of in any manner other than by
will or by the laws of descent or distribution; PROVIDED that the Administrator
may in its discretion grant transferable Nonstatutory Stock Options pursuant to
option agreements specifying (i) the manner in which such Nonstatutory Stock
Options are transferable and (ii) that any such transfer shall be subject to the
Applicable Laws.  The designation of a beneficiary by an Optionee will not
constitute a transfer.  An Option may be exercised, during the lifetime of the
Optionee, only by the Optionee or a transferee permitted by this Section 13.

     14.  ADJUSTMENTS UPON CHANGES IN CAPITALIZATION; CORPORATE TRANSACTIONS.

          (a)  ADJUSTMENT.  Subject to any required action by the stockholders
of the Company, the number of shares of Common Stock covered by each outstanding
Option, the number of shares of Common Stock that have been authorized for
issuance under the Plan but as to which no Options have yet been granted or
which have been returned to the Plan upon cancellation or expiration of an
Option, the maximum number of shares of Common Stock for which Options may be
granted to any employee under Section 8 of the Plan, and the price per share of
Common Stock covered by each such outstanding Option, shall be proportionately
adjusted for any increase or decrease in the number of issued shares of Common
Stock resulting from a stock split, reverse stock split, stock dividend,
combination or reclassification of the Common Stock, or any other increase or
decrease in the number of issued shares of Common Stock effected without receipt
of consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration."  Such adjustment shall be made by the
Administrator, whose determination in that respect shall be final, binding and
conclusive.

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Except as expressly provided herein, no issuance by the Company of shares of 
stock of any class, or securities convertible into shares of stock of any 
class, shall affect, and no adjustment by reason thereof shall be made with 
respect to, the number or price of shares of Common Stock subject to an Option.

          (b)  CORPORATE TRANSACTIONS.  In the event of the proposed dissolution
or liquidation of the Company, the Option will terminate immediately prior to
the consummation of such proposed action, unless otherwise provided by the
Administrator.  The Administrator may, in the exercise of its sole discretion in
such instances, declare that any Option shall terminate as of a date fixed by
the Administrator and give each Optionee the right to exercise his or her Option
as to all or any part of the Optioned Stock, including Shares as to which the
Option would not otherwise be exercisable.  In the event of a proposed sale of
all or substantially all of the assets of the Company, or the merger of the
Company with or into another corporation, the Option shall be assumed or an
equivalent option shall be substituted by such successor corporation or a parent
or subsidiary of such successor corporation, unless the Administrator
determines, in the exercise of its sole discretion and in lieu of such
assumption or substitution, that the Optionee shall have the right to exercise
the Option as to some or all of the Optioned Stock, including Shares as to which
the Option would not otherwise be exercisable.  If the Administrator makes an
Option exercisable in lieu of assumption or substitution in the event of a
merger or sale of assets, the Administrator shall notify the Optionee that the
Option shall be exercisable for a period of fifteen (15) days from the date of
such notice, and the Option will terminate upon the expiration of such period.

     15.  TIME OF GRANTING OPTIONS.  The date of grant of an Option shall, for
all purposes, be the date on which the Administrator makes the determination
granting such Option or such other date as is determined by the Administrator.
Notice of the determination shall be given to each Employee or Consultant to
whom an Option is so granted within a reasonable time after the date of such
grant.

     16.  AMENDMENT AND TERMINATION OF THE PLAN.

          (a)  AMENDMENT AND TERMINATION.  The Board may amend or terminate the
Plan from time to time in such respects as the Board may deem advisable.

          (b)  EFFECT OF AMENDMENT OR TERMINATION.  Any such amendment or
termination of the Plan shall not affect Options already granted and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated, unless mutually agreed otherwise between the Optionee and
the Board, which agreement must be in writing and signed by the Optionee and the
Company.

     17.  CONDITIONS UPON ISSUANCE OF SHARES.  Shares shall not be issued
pursuant to the exercise of an Option unless the exercise of such Option and the
issuance and delivery of such Shares pursuant thereto shall comply with all
relevant provisions of law, including, without limitation, the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, and the requirements of any stock exchange upon which the Shares may

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then be listed, and shall be further subject to the approval of counsel for the
Company with respect to such compliance.

          As a condition to the exercise of an Option, the Company may require
the person exercising such Option to represent and warrant at the time of any
such exercise that the Shares are being purchased only for investment and
without any present intention to sell or distribute such Shares if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned relevant provisions of law.

     18.  RESERVATION OF SHARES.  The Company, during the term of this Plan,
will at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.  The inability of the
Company to obtain authority from any regulatory body having jurisdiction, which
authority is deemed by the Company's counsel to be necessary to the lawful
issuance and sale of any Shares hereunder, shall relieve the Company of any
liability in respect of the failure to issue or sell such Shares as to which
such requisite authority shall not have been obtained.

     19.  OPTION AGREEMENT.  Options shall be evidenced by written option
agreements in such form as the Board shall approve.



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