Leading Canadian Operator Expands Business and Residential Services With Sonus Networks

Convergia Networks Lights Up New Regions of the Americas with World-Class Enterprise Services

WESTFORD, Mass., April 23, 2008 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of IP communications infrastructure solutions, today announced that Convergia Networks, a world-class provider of voice, data, and Internet services for residential, business and wholesale customers, with offices throughout North America, South America and Europe, has selected Sonus solutions as the new backbone of its international network.

Convergia selected Sonus to differentiate its service offerings, while ensuring the highest level of performance for its global customer base. Convergia will deploy Sonus' Access solution, including its recently released IMX 2.0 Multimedia Applications Platform, to deliver its ever expanding customer base with advanced residential and enterprise voice services.  Sonus' solution will enable Convergia to deliver on its vision of quality residential and business service without geographic boundaries.

"Our customers demand uncompromised network performance.  For Convergia, customer satisfaction is paramount to our success.  At the same time, we needed to differentiate our service with unique features and functionality that the IMX 2.0 can deliver," said Alejandro Bitar, president at Convergia Networks.  "The decision for us was clear: Sonus was the best solution for quality of service, scalability and reliability; and all within a network environment that is easy to operate and maintain."

Convergia's replacement of its current platform will allow Convergia to increase the performance of its network, improve customer satisfaction, reach new geographic regions and to deliver increased services.  Through Sonus' unparalleled CODEC capabilities, Convergia will be able to further improve bandwidth management and increase the overall utilization of its IP network.  Further, by integrating advanced service functionality with flexible and robust call performance quality, Sonus' IP-Voice platform will play an integral role with respect to offering the highest quality services to Convergia's customers.  

"Convergia Networks has developed one of the most comprehensive, global, end-to-end telecom networks," said Mohammed Shanableh, vice president of worldwide sales, Sonus Networks. "We share a vision of bringing innovative solutions, whether wireline, wireless or integrating both. We are proud to assist Convergia in meeting its goals of global deployment, connectivity and leading edge next generation services."

In addition to Sonus' IMX 2.0, Convergia will also deploy the Sonus GSX9000TM and GSX4000TM Open Services Switches, the PSX™ Call Routing Server, and the ASX™ Feature Server.

About Convergia Networks

Convergia Networks (www.convergia.com) is a world-class provider of voice, data, and Internet services for residential, business and wholesale customers. Via our state-of-the-art switching facilities and end-to-end network, our company presents the fullest potential of today's broadband revolution. By introducing leading edge and innovative products and services, establishing global alliances, and always striving to improve our existing business, Convergia Networks is delighting our customers worldwideTM.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of IP-voice infrastructure solutions for wireline and wireless service providers. With our 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' Annual Report on Form 10-K for the period ended December, 31, 2007, 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 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.