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Leading Voice Infrastructure Provider Recognized As the #1 Network and Telecom Technology Company on Forbes ASAP "Dynamic 100" List

WESTFORD, Mass., August 27, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure products for the new public network, today announced it has been named the most dynamic network and telecom technology company in the United States by Forbes ASAP. Published on August 20th on the Forbes.com Website, Forbes ASAP's "Dynamic 100" listing recognizes publicly held technology companies that are fueling the digital revolution with intellectual and financial capital.

"I would like to congratulate the Forbes ASAP Dynamic 2001 winners. They have positioned themselves to thrive, which is commendable in the current environment," said Patrick Dillon, editor of Forbes ASAP. "Sonus' top ranking underscores the company's leading position in the evolving telecommunications equipment space. Their commitment to providing new and innovative approaches to meet customer needs and their comprehensive business strategy gives us confidence that they will continue to succeed in the future."

Forbes ASAP has compiled the list of Dynamic 100 companies since 1998. This year's survey asked hundreds of analysts, money managers and venture capitalists to rate more than 300 companies on a scale from 1 to 5, with 5 being the top score. Sonus was the only company in the network and telecom category to receive perfect scores in three of seven categories evaluated. The top marks recognize Sonus' ability to respond to change, the strength of its people and the company's rapid growth. Sonus also rated highly in the other factors measured, including: Market Opportunity; Marketing Expertise; Alliances and Partnerships; and Financials.

"We are honored to be recognized by Forbes ASAP and to be included among such accomplished innovators," said Hassan Ahmed, president and CEO, Sonus Networks. "Being listed in the Dynamic 100 reflects the talent and dedication of the entire Sonus team, and we are proud to receive such positive recognition of the efforts of each and every employee at here at Sonus."

The full Forbes ASAP Dynamic 100 listing is currently available on Forbes' Website: www.forbes.com/asap/2001/0820/intro.html.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of voice infrastructure products for the new public network. Sonus' solutions enable service providers to deploy an integrated network capable of carrying both voice and data traffic, and to deliver a range of innovative, new services. The Sonus Open Services Architecture (OSA) and award-winning Packet Telephony suite cut the time-to-market for competitive new service products, allowing carriers and third-party developers to expand market share and build important new revenue streams. Its highly scalable products fully interoperate with and extend the life and utility of today's public network. Sonus embodies in its management and staff decades of experience in developing carrier-class voice, data and multimedia solutions for implementation in the world's largest networks. Sonus, founded in 1997, is headquartered in Westford, Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

This release may contain projections or other forward-looking statements regarding future events or the future financial performance of Sonus 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 Sonus' Quarterly Report on Form 10-Q, dated August 13, 2001, filed with the SEC, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. These risk factors include, among others, the Company's ability to grow its customer base, dependence on new product offerings, market acceptance of its products, rapid technological and market change, integration risks relating to the acquisition of telecom technologies and manufacturing and sourcing risks.

Open Services Architecture is a trademark of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated.