Sonus Networks Schedules Conference Call for First Quarter 2010 Financial Results

WESTFORD, MA, April 7, 2010 – Sonus Networks, Inc. (Nasdaq: SONS), providing network transformation through IP communications technology, today announced that it will release financial results for the first quarter of 2010 after the close of the market on Tuesday, May 4, 2010, and will host a conference call with financial analysts and investors at 4:45 p.m. ET that day.

Conference Call Details

Date: Tuesday, May 4, 2010
Time: 4:45 p.m. ET.

To listen live via telephone

Dial-in number: 800-908-9173
International Callers: +1 212-231-2900

To listen via internet

Sonus will host a live webcast of the conference call. To access the webcast, visit www.sonusnet.com, About Us, Investor Relations.

Replay Information

A telephone playback of the call will be available following the conference and can be accessed by calling 800-633-8284, or for international callers, +1 402-977-9140. The reservation number for the replay is 21465360 and will be available until May 18, 2010.

A replay of the webcast will be also available on the Sonus Networks Investor Relations website. To access the replay of the webcast, visit www.sonusnet.com, About Us, Investor Relations, Webcast Archive.

About Sonus Networks

Sonus Networks, Inc., providing network transformation through IP communications technology, is leading the evolution of communications networks to support the multi-device demands of today’s digital lifestyle. Sonus solutions and services enable fixed, mobile and cable operators to gain network awareness and new multi-media capabilities essential to retaining and expanding their subscriber base. Through standards-based interoperable solutions and services, Sonus extends the investments made in traditional networks by enabling operators to seamlessly migrate to next generation technology and deliver the secure, reliable, scalable and cost-effective network needed to grow their business. For more information, visit www.sonusnet.com

This release may contain forward-looking statements regarding future events that involve risks and uncertainties. Readers are cautioned that these forward-looking statements are only predictions and may differ materially from actual future events or results. Readers are referred to Item 1A “Risk Factors” of Sonus’ Annual Report on Form 10-K for the year ended December 31, 2009, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. Any forward-looking statements represent Sonus’ views only as of today and should not be relied upon as representing Sonus’ views as of any subsequent date. While Sonus may elect to update forward-looking statements at some point, Sonus specifically disclaims any obligation to do so, except as required by law.

Sonus is a registered trademark of Sonus Networks, Inc. All other company and product names may be trademarks of the respective companies with which they are associated.

For more information, please contact:

Fran Murphy
978-614-8148
fmurphy@sonusnet.com

Beth Panfil
978-614-8034
bpanfil@sonusnet.com