WESTFORD, MA., June 22, 2008 – Sonus Networks, Inc. (Nasdaq: SONS), a market leader in IP communications infrastructure, announced today that it is engaged in an ongoing dialogue with Legatum Capital to address the points set out by Legatum in previous communications, and to deliver a positive outcome for all shareholders of Sonus Networks.

Members of Sonus' executive management and Board of Directors met with Legatum after Sonus' Annual Shareholder Meeting on Friday, to discuss the resolution of Legatum's issues. The Company has made a formal proposal to work proactively with Legatum in a collaborative manner to resolve questions of Legatum's representation on Sonus' Board of Directors and other matters.

The Company and its Board of Directors are hopeful that an understanding can be reached with Legatum that addresses its issues while ensuring a stable and productive environment for the Company's shareholders, employees and customers. Sonus' Board believes that a quick resolution to these issues is in the best interest of all Sonus shareholders and will allow the Company to remain focused on its efforts to create increased shareholder value over time.

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 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.