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Korean Technology Leader to Provide Full Sonus Product Suite to Carrier Market

WESTFORD, Mass., May 31, 2000 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure products for the new public network, today announced that Samsung Corporation has signed an agreement to distribute and support the complete Sonus product line in the Korean market. Under terms of the contract, Samsung’s Information and Telecommunications (IT) Division will be the sole Korean provider of Sonus’ carrier-class Packet Telephony suite, including the GSX9000TM Open Services Switch, the PSX6000TM SoftSwitch, the SGX2000TM SS7 Signaling Gateway and the System 9200TM Internet offload solution.

"We’re extremely pleased to be partnering with Sonus to help Korean service providers fully realize the promise of packet telephony," said K.Y. Hwang, manager, Information and Telecommunications Services, Samsung Corporation. "Sonus delivers clear advantages over the current legacy telephony infrastructure, as well as other voice-over-packet offerings. By deploying Sonus’ award-winning solutions, carriers will not only have the ability to realign their cost structures, but also to create portfolios of enhanced, revenue-generating services."

"Samsung is recognized as a leader in introducing advanced technologies and telecom systems to Korean telecommunications organizations," commented Gary Rogers, vice president of sales and marketing, Sonus Networks. "Korea is one of the most dynamic and rapidly growing telecommunications markets in the world, and we look forward to collaborating with Samsung and its customers."

About Samsung Corporation

Samsung Corporation has dedicated itself to global business since 1938. Samsung leads Korea’s overseas trading activities and now has four major business groups: Trading, Construction, Housing Development and Internet. With the advent of the Internet, Samsung has become a leading Internet business with the largest electronic shopping mall (www.samsungmall.com) in Korea and a sophisticated cyber trading system, Merchant Intelligence System, for the import and export of goods. Samsung Corporation has aggressively formed numerous joint ventures with leading companies from around the world. The corporation often taps these strategic alliances to help it transform existing off-line businesses into cutting edge Internet companies.

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 ArchitectureTM (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 marketshare 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. 

This press release may contain forward-looking statements relating to future events or future financial performance that involve risks and uncertainties. These statements are made pursuant to the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934. These statements are only predictions and actual results could differ materially from those anticipated in these statements based upon a number of factors including those risk factors identified in Sonus Networks’ Prospectus dated May 24, 2000.

GSX9000, PSX6000, SGX2000, System 9200 and Open Services Architecture are trademarks of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated.