Sonus Networks Reports 2010 First Quarter Results

Westford, MA, May 4, 2010 – Sonus Networks, Inc. (Nasdaq: SONS), a market leader in next generation IP-based network solutions, today announced results for the quarter ended March 31, 2010.

Revenue for the first quarter of fiscal 2010 was $62.4 million, compared to $68.7 million in the fourth quarter of fiscal 2009 and $41.0 million for the first quarter of fiscal 2009. The Company's net loss on a GAAP basis for the first quarter of fiscal 2010 was $0.1 million, or $0.00 per share, compared to net income of $10.3 million, or $0.04 per diluted share, for the fourth quarter of fiscal 2009, and a net loss of $16.2 million, or $0.06 per share, for the first quarter of fiscal 2009.

"We are pleased with our strong first quarter results, which reflect the successful execution of our strategic plan," said Richard Nottenburg, President and Chief Executive Officer of Sonus Networks. "During the quarter, we continued to extend our leadership position as we added new customers, penetrated new markets and made significant enhancements to our core products and service offerings. We look forward to launching new products on our next generation platform in the near future."

Conference Call Details

Sonus Networks will host a conference call for analysts and investors to discuss its first quarter 2010 results as well as certain forward-looking information today at 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 Networks will host a live webcast of the conference call. To access the webcast, visit sonus.net, About Us, Investor Relations.

About Sonus Networks

Sonus Networks, Inc. is a leader in IP networking with proven expertise in delivering secure, reliable and scalable next generation infrastructure and subscriber solutions. With customers in over 50 countries across the globe and over a decade of experience in transforming networks to IP, Sonus has enabled service providers and enterprises to capture and retain users and generate significant ROI. Sonus products include media and signaling gateways, policy/routing servers, session border controllers and subscriber feature servers. Sonus products are supported by a global services team with experience in design, deployment and maintenance of some of the world's largest and most complex IP networks. For more information visit www.sonus.net.

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 and Form 10-Q for the quarter ended March 31, 2010, which identify 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:

Wayne Pastore
978-614-8291
wpastore@sonusnet.com

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