Leading IP Voice Services Provider Selects Sonus Networks To Effectively Scale New Voice Network

CommPartners Provides Carrier Class Wholesale Voice and Hosted IP Voice Services with Sonus Networks

WESTFORD, Mass., June 6, 2007 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider Voice over IP (VoIP) infrastructure solutions, and CommPartners, a nationwide CLEC certified, facilities based network operator providing VoIP and TDM services to carriers as well as enhanced Hosted Applications to Small and Medium sized businesses through a network of strategic partners and resellers, announced today that CommPartners has selected a Sonus-based infrastructure as the foundation of its rapidly expanding IP voice network. By deploying Sonus' distributed, IP Multimedia Subsystem (IMS)-based architecture, CommPartners is able to achieve new levels of operating efficiency, scalability, and routing flexibility, resulting in one of the United States' most robust IP wholesale and hosted services networks.

"The ability to provide carrier class performance and reliability to support the growth of our Company's carrier services and wholesale hosted IP solutions business was the most important factor in our decision-making process, and Sonus was the clear choice. No other provider of IP voice equipment carries as much traffic as Sonus or has the level of experience and expertise deploying and servicing complex IP voice networks," said Dave Clark, CEO and Co-founder, CommPartners.

CommPartners provides carrier services and wholesale IP voice services such as hosted IP PBX, IP Trunking, hosted contact center and CommPartners Connect for Linksys One including support for Local Number Portability (LNP), directory services, E-911, and domestic and international long distance backed by a proprietary Operations Support System providing real time billing and provisioning. CommPartners has selected a suite of Sonus solutions, including the GSX9000^™ Open Services Switch, PSX^™ Call Routing Server, SGX^™ Signaling Gateway, and the Sonus Insight^™ Management System.

"Because of the strong demand for today's leading IP voice services, CommPartners requires an IP backbone that enables them to scale their network without sacrificing voice quality and reliability. In addition, the Company requires a strong foundation to roll out and support enhanced new features and applications that help customers better manage their voice service," said Hassan Ahmed, chairman and CEO, Sonus Networks. "We're pleased that CommPartners, who share a similar focus on superior customer service, has selected Sonus as the foundation of their IP voice network."

CommPartners will initially deploy the Sonus-based infrastructure in New York and Los Angeles, two of their largest Points of Presence (POPs). Deployment is scheduled to begin in June 2007.

About CommPartners

CommPartners is a nationwide CLEC certified, facilities based network operator providing VoIP and TDM services to carriers as well as enhanced Hosted Applications to Small and Medium sized businesses through a network of strategic partners and resellers. 

CommPartners' IP network has been engineered to provide business-grade, IP-based voice and other value-added services. With nationwide IP network coverage, CommPartners delivers reliable, high-quality, and competitively priced carrier and wholesale hosted IP services for business including IP PBX, IPTrunking^™, hosted contact center and CommPartners Connect^™ for Linksys^® One. CommPartners' wholesale services are supported by CommPartners Management System (CMS), a scalable and automated OSS platform for multi-tiered billing and account management. The company in headquartered in Las Vegas, Nevada and is privately-held. For more information, call 702-367-VOIP (8647) or visit CommPartners' website at www.commpartners.us.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of voice over IP (VoIP) 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 dated May 8, 2006, 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 announced review of its historical stock option grants and accounting, including the impact on the Company's financial statements or results, any tax liabilities or penalties, the Company's inability to timely report with the Securities and Exchange Commission, whether the Company will file its required SEC reports by June 26, 2007 and remain listed on the NASDAQ Global Select Market, regulatory actions or litigation arising out of the review or any restatement; 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.

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.