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Company's Open Services Switch Honored in the Next-Gen Carrier Class Switch Category

WESTFORD, Mass., November 22, 1999 - Sonus Networks, the emerging leader in carrier-class packet telephony solutions, today announced that it has been selected by Internet Telephony magazine as a winner in the 1999 Product of the Year awards. Sonus' GSX9000^TM Open Services Switch was selected from a field of hundreds of entrants, in nearly 40 categories, for the prestigious award. The Internet Telephony Product of the Year awards honor innovative products and services that have contributed to the growth of the Internet telephony industry, as well as the outstanding teams who have developed and manufactured these solutions and services. 

"The Internet Telephony Product of the Year award allows us to honor exemplary products across a broad span of the marketplace," said TMC president and group publisher Rich Tehrani. "As the industry matures, we're finding more than just products and services on the market - entire solutions are being offered. We are pleased to honor the Product of the Year winners today, as they lay the groundwork for the next generation of global telecommunications." 

"Winning the Internet Telephony Product of the Year award caps a year of significant achievements for Sonus," commented Hassan Ahmed, Sonus' president and chief executive officer. "We're extremely gratified to receive this honor, which further underscores the acceptance our solutions have experienced in the marketplace." 

Sonus began shipping its innovative Packet Telephony suite, which includes the GSX9000 Open Services Switch, the PSX6000^TM SoftSwitch and the SGX2000^TM SS7 Signaling Gateway, in June 1999. In July, Global Crossing (formerly Frontier Communications) became the first major voice carrier to announce its intention to migrate its voice and telephony services to an all-packet environment. Global Crossing selected the GSX9000 as the infrastructure switch to build out the carrier's next-generation VoIP network, which is expected to be completed by year-end 2002. 

About Sonus Networks

Sonus Networks, Inc. is delivering a new class of carrier solutions that enable the movement of telephony to converged packet networks and the development of a new generation of innovative voice and data services. The award-winning Sonus Packet Telephony suite and Open Services Architecture^TM (OSA) cut the time-to-market for competitive new service products, allowing carriers and third-party developers to sustain and 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, founded in 1997, is headquartered in Westford, Massachusetts and is privately held. Additional information is available at: http://www.sonusnet.com. 

GSX9000, PSX6000, SGX2000 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.