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SETTLEMENT AGREEMENT AND MUTUAL RELEASE WITH KAREN RATTA DATED NOVEMBER 30, 1998

         This Settlement Agreement and Mutual Release ("Agreement") is 
entered into by and between SYNC RESEARCH, INC., a Delaware corporation (the 
"Company"), and Karen Ratta ("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 Vice President of 
Operations and as an Officer of the Company effective November 30, 1998 (the 
"Resignation Date"). Employee agrees to perform such projects as may be 
reasonably requested by the Chairman of the Board of the Company through the 
Termination Date at mutually convenient times for both the Company and the 
Employee. Should the Employee become an employee of another company or firm, 
or enter into a consulting arrangement and earns in excess of $100,000 prior 
to the Termination Date, all payments and participation in the benefit 
programs will cease immediately. Employee agrees to engage in employment or a 
consultant arrangement only on a non-compete basis. 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 $10,833.33 (less applicable tax withholding) each month through 
the Termination Date, in accordance with the Company's normal payroll 
practices..

         3.   STOCK OPTIONS. In consideration of the Employee's willingness 
to avail herself to the Company through the Termination Date, vesting of 
Employee's options to purchase shares 


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of Common Stock granted to Employee under the Company's Stock Option Plan 
that have not been exercised as of the date of this Agreement, shall continue 
through the Termination Date. No additional option shares shall vest after 
such date. In accordance with the terms of the Option Agreement(s) issued to 
Employee, vested options will be exercisable until 60 days after the 
Termination Date.

         4.   TERMINATION OF CHANGE OF CONTROL AGREEMENT. Effective with the 
Resignation Date, the Amended and Restated Change of Control Severance 
Agreement dated June 5, 1997 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 Termination 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 Termination Date.

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

         6.   NONCOMPETITION. Through the Termination Date, Employee will 
not, individually or as an employee, partner, officer, director or 
shareholder or in any other capacity whatsoever of or for any person, firm, 
partnership, company or corporation, other than the Company or its 
subsidiaries, own, manage, operate, sell, control or participate in the 
ownership, management, operation, sales or control of any business engaged, 
in the geographical areas referred to below, in research, development, 
marketing, sales or other activities substantially similar to or competitive 
with the business of the Company. The geographical areas in which the 
restrictions provided for in the foregoing sentence apply include all cities, 
counties and states of the United States and all other countries in which the 
Company has engaged in sales or otherwise conducted business or selling 
efforts at any time. For a period extending until one year following the 
Termination Date, Employee will not, directly or indirectly, recruit, attempt 
to hire, solicit, assist others in recruiting or hiring, 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 
she 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 Sections 2, 3 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 


<PAGE>

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, 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 the 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.

         9.   ACKNOWLEDGMENT OF WAIVER OF CLAIMS UNDER ADEA. Employee 
acknowledges that she is waiving and releasing any rights she may have under 
the Age Discrimination in 


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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 she has been advised by the writing that (a) she should 
consult with an attorney PRIOR to executing this Agreement; (b) she has at 
least twenty-one (21) days within which to consider this Agreement; (c) she 
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.

         11.  TAX CONSEQUENCES. The Company makes no representations or 
warranties with respect to the tax consequences of the payment of any such 
sums to Employee under the terms of this Agreement. Employee agrees and 
understands that she is responsible for payment, if any, of local, state 
and/or federal taxes on the sums paid hereunder by the Company and any 
penalties or assessments thereon. Employee further agrees to indemnify and 
hold the Company harmless from any claims, demands, deficiencies, penalties, 
assessments, executions, judgments, or recoveries by any government agency 
against the Company for any amounts claimed due on account of Employee's 
failure to pay federal or state taxes or damages sustained by the Company by 
reason of any such claims, including reasonable attorney's fees.

         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 


<PAGE>

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 
she 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 the confidential and proprietary information provision 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 
disparagement, criticism, 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 she 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.

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

         19.  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.

         20.  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 


<PAGE>

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 12.

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

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

         23.  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".

         24.  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.

         25.  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.

         26.  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 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.


<PAGE>

         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:VP Finance and Administration
                                             -----------------------------

                                       Dated: December 28, 1998
                                              ---------------------


                                       EMPLOYEE

                                       By /s/ Karen Ratta
                                         --------------------------
                                       Signature

                                       Karen Ratta
                                       ----------------------------
                                       Print Name

                                       Dated: December 28, 1998
                                              ---------------------