Industry Leader Unveils Solutions Designed to Unlock the Power of Mobile Broadband

WESTFORD, MA., June 17, 2008 – At NXTComm 2008, Sonus Networks (Nasdaq: SONS) the market leader in IP communications infrastructure, unveiled a complete voice solution that leverages the power of WiMAX networks to meet the unique goals of mobile broadband networks. Fully integrated and tested, the Sonus WiMAX solution promises to help operators quickly and profitably deploy voice services over their mobile broadband networks today, while getting ready for the future with 4G networks, including mobile interactive multimedia services. This voice architecture combines Sonus' leadership in IP-voice technology and the Sonus Activator.

Sonus' WiMAX solution leverages the IEEE 802.16 WiMAX standard that delivers wireless last mile access for fixed broadband services, similar to DSL or cable modem service. The Sonus WiMAX solution includes Sonus ASX, GSX, PSX, EMS, NBS and Activator that have already been proven in operators' networks around the globe and are being relied upon for real-time voice services today.

In more mature economies, operators are embracing WiMAX technology to compete against local incumbents. With the Sonus WiMAX solution these operators are now ready to deliver a complete digital package to consumers.

"At the end of 2007 there were just over 2 million WiMAX subscribers globally. That number is expected to grow to nearly 80 million by the end of 2010. The ability to add a toll quality voice service to the operators' service increases the likelihood that operators will experience even further acceleration," said Richard Webb, Directing Analyst, WiMAX, WiFi, and Mobile Devices with Infonetics research. "In more mature economies, voice based WiMAX services could significantly change the winners and losers in the region. Sonus' entrance into the market is a positive change for carriers."

Today the world's most powerful economies operate with an "always-on" mantra. Consumers and enterprises are demanding an ever increasing number of services and higher bandwidth speeds from their operators. To compete in today's global market, the ability to access the Internet and communicate is critical. Based on a standard WiMAX connectivity, the Sonus solution delivers all the capabilities individuals are accustomed to receiving via a fixed-line network, but with the benefits of IP.

"At Sonus, our mission is to change the way the world communicates. We strive to bring families, friends and colleagues closer together," said Jocelyn Philbrook, vice president, corporate marketing and investor relations. "With Sonus WiMAX, we are not only able to do that, but also to help bring world class communications to many emerging markets."

"It is apparent that WiMAX will be a key technology in the next generation of network solutions," said Vikram Saksena, CTO, Sonus Networks. "Sonus is committed to developing wireless solutions that will leverage the benefits of the WiMAX network and integrate with the world's historic telephony networks. Our new mobilEdge product and the Sonus Activator are proof of this commitment, allowing Sonus to offer a solution that incorporates service fulfillment, a crucial component in enabling operators to get to market faster and more quickly achieve return on their WiMAX investment."

To learn more about Sonus Networks IP-voice solutions for all mobile broadband delivery choices, visit booth SU9208 at NXTComm, Las Vegas, June 17th-19th 2008.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of IP-voice infrastructure solutions for wireline and wireless service providers. With its comprehensive IP Multimedia Subsystem (IMS) solution, Sonus addresses the full range of carrier applications, including residential and business voice services, wireless voice and multimedia, trunking and tandem switching, carrier interconnection and enhanced services. Sonus' voice infrastructure solutions are deployed in service provider networks worldwide. Founded in 1997, Sonus is headquartered in Westford, Massachusetts. Additional information on Sonus is available at http://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' Quarterly Report on Form 10-Q for the period ended March 31, 2008, filed with the SEC, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. Risk factors include among others: the impact of material weaknesses in our disclosure controls and procedures and our internal control over financial reporting on our ability to report our financial results timely and accurately; the unpredictability of our quarterly financial results; risks and uncertainties associated with the Company's restatement of its historical stock option granting practices and accounting including regulatory actions or litigation; risks associated with our international expansion and growth; consolidation in the telecommunications industry; and potential costs resulting from pending securities and patent litigation against the Company. 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.