H. Brian Thompson Joins Sonus Networks' Board of Directors

WESTFORD, Mass., October 28, 2003 – Sonus Networks (Nasdaq: SONS), a leading provider of carrier packet voice infrastructure solutions, today announced that it has elected H. Brian Thompson, a veteran telecommunications industry executive, to the company's board of directors.

"We are extremely pleased that Brian Thompson is joining the Sonus Networks board of directors," said Hassan Ahmed, president and CEO, Sonus Networks. "Brian has spent more than two decades in senior executive positions with leading service providers and he has been instrumental in transforming these companies into industry powerhouses. Brian's extensive experience in building successful companies, his global insight and diverse perspective make him an invaluable addition to the Sonus board of directors."

"Sonus Networks has all of the ingredients for success: industry-leading technologies, a strong customer base, highly talented employees and a huge market opportunity," commented Thompson. "Sonus is ideally positioned to become a major player in the telecommunications industry as the world's service providers make the transition to packet voice networks. I am truly pleased to join the Sonus board of directors, and look forward to working with the management team to achieve their strategic objectives."

Thompson has worked in the telecommunications industry for more than 20 years. He currently serves as chairman of the board of directors for Comsat International (CI), one of the largest independent telecommunications operators with operations throughout Latin America. He also heads his own private equity investment and advisory firm, Universal Telecommunications, Inc.

From March 1999 to September 2000, Thompson was chairman and CEO of Global Telesystems Group, Inc. He also served as chairman and CEO of LCI International, Inc. from 1991 through 1998 when LCI International merged with Qwest Communications, Inc. A former executive vice president of MCI Communications Corporation from 1981 to 1990, Thompson had responsibility for the company's eight operating divisions, including MCI International.

Thompson currently serves as a member of the board of directors of Bell Canada International, ArrayComm, Inc., Axcelis Technologies, Inc. and United Auto Group. He also serves as the co-chairman for the Americas of the Global Information Infrastructure Commission, chartered in Brussels in 1995. He spent his early career as a management consultant with McKinsey & Company, received his MBA from Harvard's Graduate School of Business, and received an undergraduate degree in chemical engineering from the University of Massachusetts.

About Sonus Networks

Sonus Networks, Inc., is a leading provider of packet voice infrastructure solutions for wireline and wireless service providers. 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 the "Cautionary Statements" section of Sonus' Quarterly Report on Form 10-Q, dated August 13, 2003 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. In addition, 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. Open Services Architecture is a trademark of Sonus Networks. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners.