For more information, please contact:

Integrated Communications Provider to Deploy Sonus Solutions to Support Long Distance Voice Services, Internet Traffic

WESTFORD, Mass. and ST. LOUIS, Mo., January 20, 2003 – Sonus Networks (Nasdaq: SONS) and NuVox Communications today announced that NuVox has chosen Sonus as its partner in building out NuVox's next-generation voice network. NuVox will use Sonus' Open Service ArchitectureTM (OSA) and packet voice infrastructure solutions to develop a VoIP (voice over IP) network that will carry all of NuVox's long distance voice traffic, as well as offload Internet traffic from NuVox's circuit-switched local voice network.

"The deployment of the Sonus product line will enable NuVox to lower its current cost structure for both capital and operating expenditures in 2003," said Paul Pitts, senior vice president of network operations, NuVox. "Leveraging the capabilities of Sonus' next-generation platform will further assist NuVox in deploying additional advanced services across all of its markets."

In building out its long distance voice network, NuVox will deploy a full set of Sonus solutions, including the GSX9000 Open Services Switch, the Insignus Softswitch and the Sonus Insight Management System. NuVox will utilize the Sonus-based network to provide long distance voice services as part of its signature product offering, the Broadband Bundle. Included in the Broadband Bundle are local and long distance voice services, dedicated high-speed Internet access, Web hosting, and e-mail. Additionally, NuVox will use the Sonus solutions to offload modem-generated Internet traffic from its local voice network, enabling them to increase the capacity of their network.

"With the new VoIP infrastructure in place, NuVox will be able to transition its long distance traffic from wholesale carriers to a NuVox-owned network," said Hassan Ahmed, president and CEO, Sonus Networks. "This solution not only offers NuVox significant financial benefits, but also provides them a migration path to deliver new and enhanced services not available in a circuit-switched environment. We are extremely pleased to provide NuVox the next-generation technologies that will enable them to achieve their business objectives."

This quarter, NuVox will begin deployment of the Sonus packet voice solutions in five major markets: Greenville, South Carolina; St. Louis, Missouri; Atlanta, Georgia; Kansas City, Missouri; and Cincinnati, Ohio. Upon successful completion of the initial deployment phase, NuVox expects to expand the network to include approximately ten additional sites. Additional terms of the contract are not being disclosed. 

About NuVox Communications

NuVox Communications is the integrated communications provider of choice, delivering superior broadband services and customer care to business customers in 30 markets in 13 Southeast and Midwest states. NuVox offers businesses and other end-users advanced integrated voice, data and Internet products and services. The Company provides dedicated and dial-up high-speed Internet access; Web page design, development and hosting; "traditional" local and long distance telephone services; and unified voice, e-mail and fax messaging as well as advanced data services. NuVox's growing product portfolio also includes LAN and WAN management, audio conferencing and remote access. NuVox provides its integrated voice and data services to over 16,000 on-net customers with more than 227,000 on-net access lines in service. NuVox's annualized revenue run rate is in excess of $148 million. NuVox, Inc. is privately held, and its headquarters are located at 16090 Swingley Ridge Road, Suite 500, in Chesterfield, MO 63017. The NuVox Communications Web site URL is www.nuvox.com.

About Sonus Networks

Sonus Networks, Inc., is a leading provider of packet voice infrastructure products for the new public network.  With its Open Services ArchitectureTM (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.

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