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SETTLEMENT AGREEMENT AND MUTUAL RELEASE

         This Settlement Agreement and Mutual Release ("Agreement") is 
entered into by and between SYNC RESEARCH, INC., a Delaware corporation (the 
"Company"), and John Rademaker ("Employee").

         WHEREAS, Employee has been employed by the Company;

         WHEREAS, the Company and Employee have entered into an agreement 
regarding confidential information and ownership of inventions (the "Employee 
Agreement");

         WHEREAS, the Company and Employee have mutually agreed to terminate 
the employment relationship and to release each other from any claims arising 
from or related to the employment relationship;

         NOW, THEREFORE, in consideration of the mutual promises made herein, 
the Company and Employee (collectively referred to as the "Parties") hereby 
agree as follows:

         1.    RESIGNATION AND TERMINATION. The Company and Employee 
acknowledge and agree that Employee will resign as Co-Chief Executive Officer 
and as an employee and as a Director of the Company effective July 31, 1998 
(the "Resignation Date"). The parties acknowledge that the Company has paid 
Employee's regular salary through the date of this Agreement in accordance 
with the Company's normal payroll practices, has paid Employee any accrued 
vacation pay and has reimbursed all expenses appropriately incurred by 
Employee on the Company's behalf. Any payments made under this Agreement 
shall be subject to withholding for taxes to the extent required under 
applicable law. Following the date of this Agreement, Employee shall not be 
entitled to any other employee benefits, including vacation, except as 
expressly set forth above and in Section 5 below.

         2.    CONSIDERATION. In consideration for the release of claims set 
forth below and other obligations under this Agreement, the Company agrees to 
pay Employee his normal salary at the rate of $16,666.67 per month (less 
applicable tax withholding) through July 31, 1998, as well as a lump sum 
payment of $216,666.67, less applicable tax withholding and less amounts owed 
by Employee to Company for legal fees and expenses incurred by the Company in 
connection with Employee's personal loan transactions (which legal fees and 
expenses total $10,899.65). Such amounts shall be paid to Employee in full 
immediately following the expiration of the seven (7) day revocation period 
provided for in Section 9 below, provided Employee does not exercise his 
revocation rights during such period.

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         3.    STOCK OPTIONS. In consideration of the amounts paid to 
Employee hereunder, Employee and the Company agree that vesting of any Option 
Agreement(s) between Employee and the Company shall continue through, and 
cease effective as of, May 31, 1998, and any such Option Agreement(s) are 
hereby amended accordingly. No additional option shares shall vest after such 
date. In accordance with the terms of the Option Agreement(s) between the 
Company and Employee, vested options will be exercisable until 60 days after 
the Resignation Date.

         4.    TERMINATION OF CHANGE OF CONTROL AGREEMENT. Effective with the 
Resignation Date, the Amended and Restated Change of Control Severance 
Agreement dated September 30, 1996 between the Company and Employee is hereby 
terminated.

         5.    BENEFITS.

               (a)   Employee shall continue to receive the Company's 
standard medical, dental and life insurance benefits through the Resignation 
Date. After such date, Employee shall have the right to continue, at his own 
expense, coverage under the Company's health insurance as provided by the 
Consolidated Omnibus Budget Reconciliation Act of 1985, as amended ("COBRA").

               (b)   Employee shall be entitled to participate in the 
Company's 401(k) Plan and Section 125 Plan until the Resignation Date.

               (c)   Employee shall not continue to accrue vacation after the 
Resignation Date.

         6.    NON-SOLICITATION. For a period extending for 18 months 
following the Resignation Date, Employee will not (a) directly or indirectly, 
recruit, solicit, assist others in recruiting, or refer to others concerning 
employment, any person who is an employee of the Company or any of its 
subsidiaries or induce or attempt to induce any such employee to terminate 
such employee's employment with the Company or any of its subsidiaries; or 
(b) solicit or accept employment or be retained by any party that, within six 
months prior to the Resignation Date, was a customer of the Company, if such 
employment or retainer involves the provision of services that are the same 
as or substantially similar to those provided by the Company. In addition, 
for a period extending for six months following the Resignation Date, 
Employee will not solicit or accept the business of any customer for which 
Employee performed services on behalf of the Company during Employee's 
employment with the Company within one year prior to the Resignation Date. 
Nothing in this Section 6 will limit Employee's right to hire former 
employees of the Company so long as Employee does not, directly or 
indirectly, recruit, solicit, assist others in recruiting or refer to others 
concerning employment, any person who is an employee of the Company or any of 
its subsidiaries or induce or attempt to induce any such employee to 
terminate such employee's employment with the Company or any of its 
subsidiaries.

         7.    NO OTHER PAYMENTS DUE. Employee acknowledges and agrees that 
he has received all salary, accrued vacation, commissions, bonuses, 
compensation, shares of stock, options therefor and other such sums due to 
Employee, other than amounts to be paid pursuant to 


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Sections 2 and 5 of this Agreement. In light of the payment by the Company of 
all wages due, or to become due to the Employee, the Parties further 
acknowledge and agree that California Labor Code Section 206.5 is not 
applicable to the Parties hereto. That section provides in pertinent part as 
follows:

                    No employer shall require the execution of any release of
                    any claim or right on account of wages due, or to become
                    due, or made as an advance on wages to be earned, unless
                    payment of such wages has been made.

         8.    RELEASE OF CLAIMS. Employee agrees that the foregoing 
consideration represents settlement in full of all outstanding obligations 
owed to Employee by the Company. Employee and the Company, on behalf of 
themselves, and their respective heirs, executors, officers, directors, 
employees, investors, shareholders, administrators, attorneys, predecessor 
and successor corporations and assigns, hereby fully and forever release each 
other and their respective heirs, executors, officers, directors, employees, 
investors, shareholders, administrators, predecessor and successor 
corporations and assigns from any claim duty, obligation or cause of action 
relating to any matters of any kind, whether known or unknown, suspected or 
unsuspected, that either of them may possess arising from any omissions, acts 
or facts that have occurred up until and including the Effective Date of this 
Agreement including, without limitation:

               (a)   any and all claims relating to or arising from 
Employee's employment relationship with the Company and termination of that 
relationship;

               (b)   any and all claims relating to, or arising from, 
Employee's right to purchase, or actual purchase of shares of stock of the 
Company;

               (c)   any and all claims for wrongful discharge of employment; 
breach of contract, both express and implied; breach of a covenant of good 
faith and fair dealing, both express and implied; negligent or intentional 
infliction of emotional distress; negligent or intentional misrepresentation 
; negligent or intentional interference with contract or prospective economic 
advantage; and defamation;

               (d)   any and all claims for violation of any federal, state 
or municipal statute, including, but not limited to, Title VII of the Civil 
Rights Act of 1964, the Age Discrimination in Employment Act of 1967, and the 
California Fair Employment and Housing Act.

               (e)   any and all claims arising out of any other laws and 
regulations relating to employment or employment discrimination; and

               (f)   any and all claims for attorney's fees and costs.

The Company and Employee agree that the release set forth in this Section 
shall be and remain in effect in all respects as a complete and general 
release as to the matters released. This release does not extend to any 
obligations incurred under this Agreement. This Agreement 


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shall not affect or limit the enforceability of any option agreement or 
option agreements now in effect between Employee and the Company or of the 
Employee Agreement.

         9.    ACKNOWLEDGMENT OF WAIVER OF CLAIMS UNDER ADEA. Employee 
acknowledges that he is waiving and releasing any rights he may have under 
the Age Discrimination in Employment Act of 1967 ("ADEA") and that the waiver 
and release is knowing and voluntary. Employee and the Company agree that the 
waiver and release does not apply to any rights or claims that may arise 
under ADEA after the Effective Date of this Agreement. Employee acknowledges 
that the consideration given for this waiver and release Agreement is in 
addition to anything of value to which Employee was already entitled. 
Employee further acknowledges that he has been advised in writing that (a) he 
should consult with an attorney prior to executing this Agreement; (b) he has 
at least twenty-one (21) days within which to consider this Agreement; (c) he 
has a least seven (7) days following the execution of this Agreement by the 
parties to revoke this Agreement; and (d) this Agreement shall not be 
effective until the revocation period has expired.

         10.   CIVIL CODE SECTION 1542. The parties represent that they are 
not aware of any claim by either of them other than the claims that are 
released by this Agreement. Employee and the Company acknowledge that they 
are familiar with the provisions of California Civil Code Section 1542, which 
provides as follows:

               A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR
               DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
               EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
               AFFECTED HIS SETTLEMENT WITH THE DEBTOR.

Employee and the Company, being aware of such code section, agree to waive 
any rights they may have thereunder, as well as under any other stature or 
common law principles of similar effect. In connection with such waiver and 
relinquishment, the parties hereby acknowledge that they are aware that they, 
or their attorneys, may hereafter discover claims or facts in addition to or 
different from those which they now know of or believe to exist with respect 
to the subject matter of this Agreement, but that their intention is to 
hereby fully, finally and forever settle and release all of the disputes and 
differences, known or unknown, suspected or unsuspected, which do now exist, 
which may exist in the future, or which heretofore have existed between the 
parties. In furtherance of such intention, the releases herein given shall be 
and remain in effect as a full and complete general release, notwithstanding 
the discovery or existence of any such additional or different claims or 
facts. The parties acknowledge that they separately bargained for the 
foregoing waiver of the provisions of Section 1542 of the California Civil 
Code.

         11.   TAX CONSEQUENCES. The Company makes no representations or 
warranties with respect to the tax consequences of the payment of any sums to 
Employee under the terms of this Agreement. Employee agrees and understand 
that he is responsible for payment, if any, of local, state and/or federal 
taxes on the sums paid hereunder by the Company and any penalties 


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or assessments thereon.

         12.   CONFIDENTIALITY. The parties agree to use their best efforts 
to maintain in confidence the existence of this Agreement, the contents and 
terms of this Agreement, and the consideration for this Agreement. 
Notwithstanding the foregoing, the Employee shall be permitted to discuss 
provisions of this Agreement in confidence with his attorneys, accountants, 
tax advisors and spouse.

         13.   NONDISCLOSURE OF CONFIDENTIAL AND PROPRIETARY INFORMATION. 
Employee shall continue to maintain the confidentiality of all confidential 
and propriety information of the Company as provided by the Employee 
Agreement previously entered into between the Company and the Employee, a 
copy of which is attached hereto as Exhibit A. Employee agrees that at all 
times hereafter, Employee shall not intentionally divulge, furnish or make 
available to any party any of the trade secrets, patents, patent 
applications, price decisions or determinations, inventions, customers, 
proprietary information or other intellectual property rights of the Company, 
until after such time as information has become publicly known otherwise than 
by act of collusion of Employee. Employee further agrees that he will return 
all the Company's property and confidential and proprietary information in 
his possession to the Company within five business days after the Resignation 
Date.

         14.   BREACH OF THIS AGREEMENT. Employee acknowledges that upon 
breach of any of the confidential and proprietary information provisions 
contained in Section 13 of this Agreement, the Company would sustain 
irreparable harm from such breach, and, therefore, Employee agrees that in 
addition to any other remedies which the Company may have for any breach of 
this Agreement or otherwise, including termination of the Company's 
obligations to provide benefits to Employee as described in Sections 2, 3 and 
5 of this Agreement, the Company shall be entitled to obtain equitable 
relief, including specific performance and injunctions, restraining Employee 
from committing or continuing any such violation of this Agreement.

         15.   NON-DISPARAGEMENT. Each party agrees to refrain from any 
defamation, slander of the other, or tortious interference with the contracts 
and relationships of the other.

         16.   AUTHORITY. The Company represents and warrants that the 
undersigned has the authority to act on behalf of the Company and to bind the 
Company and all who may claim through it to the terms and conditions of this 
Agreement.  Employee represents and warrants that he has the capacity to act 
on his own behalf and on behalf of all who might claim through him to bind 
them to the terms and conditions of this Agreement. Each Party warrants and 
represents that there are no liens or claims of lien or assignments in law or 
equity or otherwise of or against any of the claims or causes of action 
released herein.

         17.   NO REPRESENTATIONS. Each party represents that it has 
carefully read and understands the scope and effect of the provisions of this 
Agreement. Neither party has relied upon any representations or statements 
made by the other party which are not specifically set forth in this 
Agreement.


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         18.   COSTS. The Parties shall each beach their own costs, 
attorneys' fees and other fees incurred in connection with this Agreement.

         19.   INDEMNIFICATION. The Company will continue to provide 
indemnification and other benefits to Employee to the extent required under 
the Indemnification Agreement between Employee and the Company dated November 
6, 1995.

         20.   SEVERABILITY. In the event that any provision hereof becomes 
or is declared by a court of competent jurisdiction to be illegal, 
unenforceable or void, this Agreement shall continue in full force and effect 
without said provision.

         21.   ENTIRE AGREEMENT. This Agreement represents the entire 
agreement and understanding between the Company and Employee concerning 
Employee's separation from the Company and supersedes and replaces any and 
all prior agreements and understandings concerning Employee's relationship 
with the Company and his compensation by the Company other than any option 
agreement as described in Section 3 and other than the Employee Agreement as 
described in Section 13.

         22.   NO ORAL MODIFICATION. This Agreement may only be amended in 
writing signed by Employee and the Company.

         23.   GOVERNING LAW. This Agreement shall be governed by the laws of 
the State of California.

         24.   EFFECTIVE DATE. This Agreement shall be effective once it has 
been signed by both parties and such date is referred to herein as the 
"Effective Date".

         25.   COUNTERPARTS. This Agreement may be executed in counterparts, 
and each counterpart shall have the same force and effect as an original and 
shall constitute an effective binding agreement on the part of each of the 
undersigned.

         26.   ASSIGNMENT. This Agreement may not be assigned by Employee or 
the Company without the prior consent of the other party. Notwithstanding the 
foregoing, this Agreement may be assigned by the Company to a corporation 
controlling, controlled by or under common control with the Company without 
the consent of Employee.

         27.   VOLUNTARY EXECUTION OF AGREEMENT. This Agreement is executed 
voluntarily and without any duress or undue influence on the part or behalf 
of the parties hereto, with the full intent of releasing all claims. The 
parties acknowledge that:

               (a)   They have read this Agreement;

               (b)   They have been represented in the preparation, 
negotiation and execution of this Agreement by legal counsel of their own 
choice or that they have voluntarily declined to 


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seek such counsel;

               (c)   They understand the terms and consequences of this
Agreement and of the releases it contains; and

               (d)   They are fully aware of the legal and binding effect of
this Agreement.


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     IN WITNESS WHEREOF, the parties have executed this Agreement on the 
respective dates set forth below.


                                     SYNC RESEARCH, INC.


                                     By: /s/ WILLIAM K. GUERRY
                                        ----------------------------------

                                     Title: V.P. Finance
                                           -------------------------------

                                     Dated: September 23, 1998
                                           -------------------------------


                                     EMPLOYEE

                                     /s/ JOHN RADEMAKER
                                     --------------------------------------
                                     Signature

                                     John Rademaker
                                     --------------------------------------
                                     Print Name

                                     Dated: September 28, 1998
                                           --------------------------------


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