WESTFORD, Mass., August 6, 2008 – Sonus Networks, Inc. (Nasdaq: SONS), a market leader in IP communications infrastructure solutions, announced today that the Gartner "Magic Quadrant for Softswitch Architecture" report (Bettina Tratz-Ryan, et al, August 4, 2008), which studies vendors in the softswitch architecture industry, has positioned Sonus in the "Leaders" quadrant.

"Over the last 10 years, we have seen many companies enter and leave this market, but we have remained focused on delivering technology that helps to drive our customers' businesses forward," said Vikram Saksena, CTO of Sonus Networks. "Growth for Sonus over the last 12 months has been driven by success in new geographic markets and emerging fields such as access and wireless. In my opinion, it is this ability to assess, innovate and execute against the market opportunity that keeps Sonus ahead in the leader's quadrant."

With five of the six largest global network operators relying on Sonus technology to deliver services to their customers everyday, Sonus offers a portfolio of carrier-class IP-based voice solutions for wireline and wireless network operators, Internet Service Providers (ISPs), and cable operators. Sonus offers complete solutions for IP based core and access networks, as well as a robust platform for the delivery of enhanced next generation services.

About the Gartner Magic Quadrant

The Magic Quadrant is copyrighted 2008, by Gartner, Inc. and is reused with permission. The Magic Quadrant is a graphical representation of a marketplace at and for a specific time period. It depicts Gartner's analysis of how certain vendors measure against criteria for that marketplace, as defined by Gartner. Gartner does not endorse any vendor, product or service depicted in the Magic Quadrant, and does not advise technology users to select only those vendors placed in the "Leaders" quadrant. The Magic Quadrant is intended solely as a research tool, and is not meant to be a specific guide to action. Gartner disclaims all warranties, express or implied, with respect to this research, including any warranties of merchantability or fitness for a particular purpose.

About Sonus Networks

Sonus Networks, Inc. is a market leader in IP communications infrastructure 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; actions that may be taken by significant shareholders; 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.