EXHIBIT 10.1

September 6, 2007

PERSONAL AND CONFIDENTIAL

Ellen B.Richstone

Dear Ellen:

This letter agreement “(Agreement”) will confirm the terms of your separation of
employment from Sonus Networks, Inc. (“Sonus” or the “Company”).

1.                                       Employment Status and Final Payments. 
Your employment with the Company shall terminate following a transition period
to be determined by the Parties. On the Separation Date (date to be determined),
the Company shall pay you (i) all earned but unpaid salary payments up to the
Separation Date, and (ii) all accrued but unused vacation pay, in accordance
with the Company’s vacation policy.

2.                                       Payments.  After your Separation Date,
subject to your execution of this Agreement and the expiration of the seven (7)
day revocation period described below, you will receive a lump sum payment of
$273,156, (calculated as one year of your current annualized base salary). All
payments set forth in this Agreement shall be subject to all applicable federal,
state and/or local withholding and/or payroll taxes.  Nothing in this Agreement
shall be construed to require the Company to make any payments to compensate you
for any adverse tax effect associated with any payment or benefits or for any
deduction or withholding from any payment or benefit.

3.                                       Health Benefits.  Your current health
benefits (medical, dental and vision) will continue through the end of the month
in which you are separated. After this date, you will have the right to continue
your coverage by electing COBRA.  If you choose to elect COBRA, all insurance
premiums and any administrative fees associated therewith, shall be your sole
responsibility.

4.                                       Benefits Cessation.  As of the
Separation Date, the following benefits cease to be effective:  vacation
accrual, sick and personal day accrual, 401k, life and accidental death and
dismemberment, flexible spending accounts and short-term/long-term disability.  
You are advised to consult Sonus’ Human Resources Department with respect to
your rights to continue certain benefits at your own expense.

5.                                       Stock Options.  As set forth in the
Company’s Stock Option and Incentive Plan (the “Plan”) and the stock option
agreement(s) between you and the Company (the “Option Agreements”), your options
to purchase the Company’s common stock shall cease vesting on the

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Separation Date.  You will have 12 months from the date of termination to
exercise your outstanding vested shares.

6.                                       Stock Transactions.  As of the
Separation Date, you will no longer be obligated to comply with the Company’s
trading black out restrictions regarding the purchase or sale of the Company’s
stock or the exercise of stock options, although you will continue to be subject
to laws regarding insider trading.

7.                                       401(k) Plan.  All contributions to the
Sonus Networks 401(k) Plan will continue through your Separation Date.  You will
be allowed under the plan to maintain your accumulated Sonus Networks 401(k)
account funds in your Sonus Networks 401(k) account for an unspecified amount of
time, or until you close the account, unless the Sonus Networks 401(k) Plan
provides for a specified end date by which you must withdraw or rollover your
account funds.  If your balance is less than $5,000.00, you will need to
rollover your money or take a distribution.

8.                                       Company Property.   On or before the
Separation Date, you agree to return to the Company all Company property and
materials, including but not limited to, personal computers, laptops, diskettes,
intangible information stored on diskettes, software programs and data compiled
with the use of those programs, software passwords or codes, tangible copies of
trade secrets and confidential information, telephone charge cards, manuals,
building keys and passes, names and addresses of all Company customers and
potential customers, customer lists, customer contacts, sales information,
memoranda, sales brochures, business or marketing plans, reports, projections,
and any and all other information or property previously or currently held or
used by you that is or was related to your employment with the Company.  You may
retain your cellular phone, Blackberry and related equipment. You agree that if
you discover any other Company or proprietary materials in your possession after
the Separation Date, you will immediately notify the Company and return such
materials to the Company.

9.                                       Business Expenses.  The Company will
also reimburse you for all appropriately documented business expenses, including
dues renewal and seminar fees, incurred through your Separation Date, in
accordance with Company policy.  You will be required to complete a Sonus
expense report and submit it to me no later than thirty (30) days after your
Separation Date.

10.                                 Contractual Obligations.  Your Sonus
Non-competition and Confidentiality Agreement continues in effect, per its
terms, after your separation of employment and you continue to be bound by all
pertinent provisions thereof.

11.                                 Cooperation.  You agree to cooperate with
and assist the Company in any administrative or judicial proceedings involving
the Company, including but not limited to making your self available at
reasonable times upon reasonable notice for meetings with counsel, depositions
and court appearances.  The Company agrees to take all reasonable steps to
insure that any required assistance does not interfere with any other work in
which you may then be engaged.  In consideration of the releases and other
commitments made by and between the parties as set forth in this Agreement,
Sonus will pay your costs and expenses, including reasonable attorneys’ fees,
incurred in connection with any claim, lawsuit, formal or informal
investigations, subpoena, regulatory proceeding or any pother proceeding which
arises out of or

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is related to the Company’s activities during your employment.  Sonus’
obligation to pay such fees shall be conditioned upon your continued compliance
with the terms of this Agreement.

12.                                 Non-Disparagement Obligations.  You agree
not to take any action or make any statement, written or oral, which disparages
or criticizes the Company, its management, directors, investors, or any other
parties involved in a business relationship with the Company, or its practices,
or which disrupts or impairs the Company’s normal operations, including actions
or statements that would (1) harm the reputation of the Company with its current
and prospective customers, distributors, suppliers, other business partners, or
the public; or (2) interfere with existing contractual or employment
relationships with current and prospective customers, suppliers, distributors,
other business partners or Company employees. Sonus will instruct its’ directors
and officers, and those employees made privy to the terms of this Agreement not
to make any statements, orally or in writing, which disparage you and damage
your personal or professional reputation.

13.                                 Release:  In exchange for the consideration
provided herein, and other good and valuable consideration, the receipt of which
you hereby acknowledge, you hereby agree that you and your representatives,
agents, estate, heirs, successors and assigns (“You”) release, remise,
discharge, indemnify and hold harmless the Releasees (defined to include Sonus
Networks, Inc., its predecessors, successors, parents, subsidiaries, divisions,
affiliates, assigns, plan sponsors and plan fiduciaries, and its and their
current and former directors, shareholders, investors, fiduciaries, officers,
employees, representatives, attorneys and/or agents, all both individually, in
their capacity acting on the Company’s behalf, and in their official
capacities), of and from any and all actions or causes of action, suits, claims,
complaints, obligations, liabilities, contracts, agreements, promises, debts and
damages, whether existing or contingent, known or unknown, suspected or
unsuspected, arising up to and including the date of execution of this
Agreement, including, but not limited to, any and all claims arising out of or
in connection with (i) your employment and separation from employment with the
Company; (ii) any federal, state or local law, constitution or regulation
regarding either securities, employment, employment benefits, or employment
discrimination and/or retaliation including, without limitation, those laws or
regulations concerning discrimination on the basis of race, color, creed,
religion, age, sex, sex harassment, sexual orientation, genetic information,
national origin, ancestry, handicap or disability, veteran status or any
military service or application for military service; (iii) any contract,
whether oral or written, express or implied, any tort, whistleblower claim or
common law claim; and (iv) your ownership of the Company’s stock.  This release
is intended by You to be all encompassing and to act as a full and total release
of any claims, whether specifically enumerated herein or not, that You have, may
have or have had against the Releasees up to the date of execution of this
Agreement.  Notwithstanding the above, this release does not apply to the
enforcement of:  (i) this Agreement; (ii) your Stock Options Agreement; (iii)
your Indemnity Agreement; or (iv) any indemnification provision contained in any
relevant by-law of the Company.

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14.                                 Waiver of Rights and Claims Under the Age
Discrimination in Employment Act of 1967. As you are 40 years of age or older,
you are being informed that you have or may have specific rights and/or claims
under the Age Discrimination in Employment Act of 1967 (ADEA) and you agree
that:

(a)                                  in consideration for the consideration
provided herein, you specifically and voluntarily waive such rights and/or
claims under the ADEA you might have against the Releasees to the extent such
rights and/or claims arose prior to the date this Agreement was executed;

(b)                                 you understand that rights or claims under
the ADEA which may arise after the date this Agreement is executed are not
waived by you;

(c)                                  you are advised that you have at least 21
days within which to consider the terms of this Agreement and to consult with or
seek advice from an attorney of your choice or any other person of your choosing
prior to executing this Agreement and that such 21-day review period will not be
affected or extended by any revisions, whether material or immaterial, that
might be made to this Agreement;

(d)                                 in entering into this Agreement you are not
relying on any representation, promise or inducement made by the Company or its
attorneys with the exception of those promises described in this document.

(e)                                  you may revoke this Agreement for a period
of seven (7) days following your execution hereof and all rights and obligations
of both parties under this Agreement shall not become effective or enforceable
until the seven (7) day revocation period has expired.

15.                                 Accord and Satisfaction.  You agree that the
payments and benefits set forth in this Agreement, together with payments and
benefits the Company previously provided to you, are complete payment,
settlement, accord and satisfaction with respect to all obligations and
liabilities of the Releasees to You, and with respect to all claims, causes of
action and damages that could be asserted by You against the Releasees regarding
your employment or separation from employment with the Company, including,
without limitation, all claims for wages, salary, commissions, draws, car
allowances, incentive pay, bonuses, business expenses, vacation, stock, stock
options, severance pay, attorneys’ fees, compensatory damages, exemplary
damages, or other compensation, benefits, costs or sums.

16.                                 Entire Agreement. This Agreement is the
entire agreement between you and the Company, and all previous agreements or
promises between you and the Company are superseded, null and void, except for
the Non-Compete Agreement, the Option Agreement(s) and the Plan, each of which
shall remain in full force and effect in accordance with their respective terms.

17.                                 Choice of Law.  The law of the Commonwealth
of Massachusetts will govern any dispute about this Agreement, including any
interpretation or enforcement of this Agreement, and you hereby submit to the
jurisdiction and venue of any Massachusetts court.

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18.  General Terms.  In the event of any dispute, this Agreement will be
construed as a whole, will be interpreted in accordance with its fair meaning,
and will not be construed strictly for or against either you or the Company. 
This Agreement may not be changed, amended, modified, altered or rescinded
except upon the express written consent of both you and an authorized Company
officer.  Any waiver of any provision of this Agreement by the Company shall not
constitute a waiver of any other provision of this Agreement unless the Company
expressly so indicates otherwise.  This Agreement shall not be assigned to you
but shall be binding on the parties hereto and their respective heirs, legal
representatives, successors and assigns and shall inure to the benefit of the
Company’s successors and assigns.  If one or more of the provisions contained in
this Agreement shall for any reason be held to be excessively broad as to scope,
activity, subject or otherwise so as to be unenforceable at law, such provision
or provisions shall be construed by the appropriate judicial body by limiting or
reducing them, so as to be enforceable to the maximum extent compatible with the
applicable laws as it shall then appear.

Very truly yours,

SONUS NETWORKS, INC.

 

 

 

 

 

 

 

 

By:

/s/ Hassan Ahmed

 

 

 

 

 

 

 

 

 

 

Hassan Ahmed

 

 

 

 

 

Chief Executive Officer

 

 

 

YOU REPRESENT THAT YOU HAVE READ THE FOREGOING AGREEMENT, THAT YOU FULLY
UNDERSTAND THE TERMS AND CONDITIONS OF SUCH AGREEMENT AND THAT YOU ARE
VOLUNTARILY EXECUTING THE SAME.  IN ENTERING INTO THIS AGREEMENT, YOU DO NOT
RELY ON ANY REPRESENTATION, PROMISE OR INDUCEMENT MADE BY THE RELEASEES WITH THE
EXCEPTION OF THE CONSIDERATION DESCRIBED IN THIS DOCUMENT.

Accepted and agreed:

By:

/s/ Ellen B. Richstone

 

September 6, 2007

 

 

Ellen B. Richstone

 

Date

 

 

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IF YOU DO NOT WISH TO USE THE 21-DAY PERIOD,

PLEASE CAREFULLY REVIEW AND SIGN THIS DOCUMENT

I, Ellen Richstone, acknowledge that I was informed and understand that I have
21 days within which to consider the attached Agreement, have been advised of my
right to consult with an attorney regarding such Agreement and have considered
carefully every provision of the Agreement, and that after having engaged in
those actions, I prefer to and have requested that I enter into the Agreement
prior to the expiration of the 21 day period.

 

Dated:

September 6, 2007

 

 

/s/ Ellen B. Richstone

 

 

 

Ellen B. Richstone

 

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