Welltech to Provide Complete Set of Sonus Solutions to Taiwan Carrier Market; Sonus and Welltech to Host Joint Seminar on Packet Voice Technology and Enhanced Services

WESTFORD, Mass., November 11, 2002 - Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that it has formed a distribution relationship with Welltech Computer Corporation. Under this non-exclusive agreement, Welltech will provide the full range of Sonus packet voice products to the Taiwanese carrier market, including Sonus' award-winning GSX9000^TM Open Services Switch, the Insignus^TM Softswitch, and the Sonus Insight^TM Element Management System. A leading company in CTI (computer telephony integration) technology in Taiwan, Welltech brings deep experience in systems development, and has developed its own line of call center solutions.

"Asia continues to be one of the most active of the world's telecommunications markets, and our relationship with Welltech expands our presence in the region," said Gary Rogers, vice president, worldwide sales, Sonus Networks. "We look forward to working closely with Welltech to help carriers in Taiwan build out the next-generation packet voice networks that will enable them to compete more effectively in the global market."

"Sonus is clearly recognized as the worldwide market leader in carrier-class packet voice solutions, and its range of solutions delivers clear advantages over other alternatives available today," said John Chen, CEO, Welltech. "By adding Sonus' solutions to our product portfolio, we will enable our carrier customers to enhance their businesses through the rapid development and delivery of highly competitive new services, while also significantly reducing their ongoing network operations costs."

To promote the benefits of voice over IP (VoIP), Sonus and Welltech will be holding a half-day seminar that focuses on next-generation packet telephony and the enhanced services enabled by packet voice. The seminar will be held in Taipei on Thursday, November 21, 2002 and will feature presentations by Welltech CEO John Chen and Sonus director Jim Huang.

About Welltech Computer

Welltech Computer Co., Ltd. was founded in 1988 in the capital of Taiwan with the aim of linking people and technologies, and has been an integral part of the community for over a decade. Welltech is committed to promoting better communications and networking solutions to its customers through the company's strong knowledge and expertise in VoIP, CTI and Call Center. Welltech is an ISO 9001 certified company.

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^TM (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 November 13, 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 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.

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