SUPERCOMM 2002 Booth #32316, Hall A3

Live Booth Demonstrations Highlight Access, Cable, Trunking and Enhanced Services Applications; Sonus' GSX9000 Open Services Switch and Insignus Softswitch Featured in ISC SUPERDemo

WESTFORD, Mass., June 3, 2002 - Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, is demonstrating a wide array of next-generation packet voice solutions and services at the SUPERCOMM 2002 exhibition being held June 4-6, 2002 in Atlanta, Georgia. The Sonus exhibit features live IP-to-PSTN network demonstrations of the company's award-winning trunking and access solutions, as well as infrastructure and enhanced services provided by 27 members of Sonus' Open Services Partner AllianceSM (OSPA).

"In today's market environment, service providers are increasingly focused on reducing their network costs and more importantly, rapidly building new revenues," said Terri Griffin, vice president, marketing, Sonus Networks. "Packet voice addresses both of these carrier challenges, and at SUPERCOMM, we're showcasing the comprehensive packet voice solutions that carriers can deploy today to build advanced, next-generation networks that span from trunking applications to feature-rich access services."

In its booth, Sonus is highlighting its Open Services Architecture (OSA) and solutions, which address a broad set of carrier applications, such as long distance/international, residential/Centrex and tandem switching, and which currently drive more than 2.5 billion minutes of traffic over carrier networks each month. At the foundation of these solutions are Sonus' GSX9000 Open Services Switch, the Insignus Softswitch and the Sonus Insight Management System.

At the show, Sonus has a live demonstration of its SMARRT Access solution, a complete end-to-end packet voice solution for carriers deploying local voice networks, which is based on the company's Insignus ASX Access Server. Sonus is also showcasing its voice over broadband capabilities, with live interoperability demonstrations of its new SMARRT Cable solution working in conjunction with a range of PacketCable-compliant headend and customer premises equipment from the industry's leading cable vendors (see related announcement "Sonus Networks Introduces SMARRT Cable Solution at SUPERCOMM 2002").

With a number of its OSPA Platinum and Powered Partners, Sonus is featuring five of the industry's leading revenue-generating IP-based services running over a live network. Enhanced services and partners highlighted in the exhibit include: hosted IP PBX from Sylantro Systems; unified communications from BayPackets; prepaid calling card services from Pactolus Communications Software; voice conferencing from Voyant Technologies; and call center/ACD services from NetCentrex. Additionally, the Packet Time Caf' in Sonus' booth displays the latest IP phones and integrated access devices (IADs) from OSPA partners, allowing SUPERCOMM attendees to make calls anywhere in the world using the live packet voice network.

In the International Softswitch Consortium SUPERDemo (Booth #24476, Hall B5), Sonus is demonstrating its packet voice infrastructure solutions working in conjunction with enhanced services from its OSPA Powered Partner, Sylantro Systems. The combination of Sonus' GSX9000 Open Services Switch and Insignus Softswitch, and Sylantro's Applications Switch platform offers carriers an advanced class of managed telephony services that replace today's in-house PBX and key system offerings, allowing them to deliver new applications to generate new revenues.

About Sonus Networks

Sonus Networks, Inc., is a leading provider of packet voice infrastructure products for the new public network. With its Open Services Architecture (OSA), Sonus delivers end-to-end solutions addressing a full range of carrier applications, including trunking, residential access and Centrex, tandem switching, and IP voice termination, as well as enhanced services. Sonus' award-winning voice infrastructure solutions, including media gateways, softswitches and network management systems, are deployed in service provider networks worldwide. 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 May 10, 2002 and 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 adverse effect of recent developments in the telecommunications industry, the weakened financial position of many emerging service providers, Sonus' ability to grow its customer base, dependence on new product offerings, market acceptance of its products, rapid technological and market change and manufacturing and sourcing risks.

Open Services Partner Alliance is a service mark of Sonus Networks. Open Services Architecture, SMARRT, GSX9000, Insignus and Sonus Insight are trademarks of Sonus Networks. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners.