WESTFORD, Mass., August 9, 2007 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider Voice over IP (VoIP) infrastructure solutions, today announced the appointment of Mohammed Shanableh as interim vice president, worldwide sales, for Sonus Networks effective immediately, replacing Jim Collier. Shanableh was previously the Company’s vice president, worldwide sales engineering.

Shanableh will report directly to Chairman, President and CEO Hassan Ahmed, and is tasked with expanding Sonus' presence with global tier one operators. Shanableh brings to this role a wealth of execution experience and possesses a strong complement of operational and leadership skills. Most recently, he served as Sonus' vice president of worldwide sales engineering, where he led the Company's business initiatives with incumbent operators globally. Responsible for Sonus' global sales engineering organizations and all customer-facing engineering functions, Shanableh has aggressively driven the Company's broadened geographic sales initiatives. He joined Sonus in 2004 from Telica, now Alcatel-Lucent, where he was responsible for Customer Carrier Strategy, and prior to Telica, Shanableh was the co-founder of Valiant Networks.

"We are all extremely pleased to have Mohammed take on this role," said Hassan Ahmed, Chairman, President and CEO, Sonus Networks. "With nearly 15 years of insight and expertise in the telecommunication industry, Mohammed has the experience and energy that is ideal for this role. In the past 3 years, he has driven close partnerships with virtually all of our customers and has built strong presence within the largest operators in the world. Adding someone of Mohammed's caliber to the worldwide sales leadership role will enhance our focus and execution on a global scale."

"Sonus is a recognized leader in the industry, with a proven portfolio of products, outstanding people and an enviable market position," added Shanableh. "It is exciting to be part of the organization that is redefining communications. There is incredible opportunity in the IP-Voice market and I am eager to begin driving our solutions further into customer networks."

"As we continue to advance Sonus' position in the industry, we are committed to building the best possible team and making the changes to the executive management team are in the best interests of the Company and all of its stakeholders, including our investors, customers and employees," added Ahmed. "We have a tremendous opportunity and our customers have a great deal of urgency to move their networks forward. As an executive team, we are all completely committed to driving the development and deployment of one of the most powerful portfolios in the industry."

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 contains 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 second quarter of 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; whether the Company will remain listed on the NASDAQ Global Select Market; regulatory actions or litigation arising out of the Company's voluntary stock option review and related 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. All other company and product names may be trademarks of the respective companies with which they are associated.