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SUPERCOMM Booth #7315

BroadBand Office Deploys Sonus’ Complete Packet Telephony Suite for Access and Long Distance Services

WESTFORD, Mass., June 6, 2000 – Sonus Networks (Nasdaq: SONS) and BroadBand Office, Inc. ("BBO") today announced that BBO has selected Sonus’ carrier-class packet telephony solutions to deliver voice services throughout BBO’s national network. BBO, a leading global provider of communications, Internet and e-business solutions, will be deploying Sonus’ voice infrastructure products to provide facilities-based voice services (local and long distance) in more than 30 major metropolitan markets across the nation. 

"We wanted a packet-driven, next generation-based switching platform that provided us with the scalability, flexibility, and manageability that BBO customers would demand. Sonus fit the bill," said Johnson Agogbua, BBO vice president of engineering. "Sonus will provide its voice-over-IP trunking gateway, SS7 gateway and soft switch capabilities in our advanced network architecture. BBO’s goal is to provide a full suite of voice services for our customers that encompass not only the Class 5, 4, and 3 capabilities of a traditional network, but also to enable IP telephony-to-the-desktop. Sonus’ platforms serve as the cornerstone of this architecture." 

By deploying Sonus’ Packet Telephony suite, including the GSX9000TM Open Services Switch, the PSX6000TM SoftSwitch and the SGX2000TM SS7 Signaling Gateway throughout its network, BBO will be able to roll out local and long distance voice services more cost effectively and rapidly than with traditional alternatives. Additionally, with the Sonus-based network, BroadBand Office will also be well-positioned to offer enhanced voice services in the future.

"BroadBand Office brings to business customers a unique value proposition, with its innovative portfolio of communications and applications services," commented Hassan Ahmed, Sonus’ president and CEO. "We’re thrilled that BroadBand Office has selected our infrastructure solutions as the platform for delivering critical voice services to enterprises throughout the United States."

BroadBand Office plans to begin deployment of the Sonus solutions in selected metropolitan markets in the second quarter. Terms of the agreement were not disclosed.

About BroadBand Office, Inc.

BroadBand Office, Inc. was launched in July 1999 by leading venture capital firm Kleiner Perkins Caufield & Byers and eight of the country’s largest real estate companies. BBO’s core business is to enable customers to simply plug into a BBO wall jack and immediately have access to a full range of advanced communications, Internet and e-business solutions. BBO offerings include local, long distance, and wireless voice services, dedicated Internet access, and advanced Internet services including remote access, virtual private networks (VPN), web hosting, video, and e-business solutions. BBO’s footprint spans 25 percent of all the commercial office space in the United States. BBO began providing service in late 1999, and is currently rolling out its services nationally. More information about BBO can be found on the World Wide Web at: www.bbo.com. 

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 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.