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IP Unity, NetCentrex and RADCOM Complete Interoperability Testing with Sonus Solutions

WESTFORD, Mass., December 10, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that three members of its Open Services Partner Alliance^SM (OSPA) have recently attained the "Powered" partner designation for proven integration with Sonus products. Solutions from IP Unity, NetCentrex and RADCOM (Nasdaq: RDCM) have successfully passed rigorous interoperability tests with Sonus products in the company's OSPA Interoperability Lab located in Richardson, Texas. 

The OSPA's mission is to help empower standards-based interoperability between applications, third-party vendors and Sonus products. Sonus' OSPA Interoperability Lab is uniquely positioned to test packet voice solutions through the use of state-of-the-art testing equipment within environmentally controlled facilities. Once an OSPA member demonstrates interoperability with a Sonus product, the partner becomes "Powered." Sonus and its "Powered" partners offer service providers with end-to-end packet-based network solutions using best-of-breed technologies and applications.

"Interoperability testing is integral to the strength of our OSPA program - the fully integrated and proven solutions delivered by Sonus and our Powered partners allow carriers to more rapidly and easily reap the benefits of packet voice architectures," said Terri Griffin, vice president, marketing, Sonus Networks. "We congratulate IP Unity, NetCentrex and RADCOM for taking their partnerships to the next level and further demonstrating their commitment to helping carriers build effective, next-generation converged networks."

The three most recent products to earn "Powered" status in the OSPA include:

• The IP Unity Harmony6000^(TM) Application Server is a scalable carrier-class, hardware and software-based platform that enables service providers to deliver enhanced voice, data and web-enabled applications and services over IP and PSTN networks. The Harmony 6000 application server works in conjunction with softswitch platforms to deliver revenue-generating enhanced services, such as conferencing, over IP networks. (www.ipunity.com)    
• NetCentrex Saga800 enables service providers to deliver next-generation network-based eCRM infrastructure for multi-media contact centers, allowing enterprises to offer superior customer service via a comprehensive and flexible contact management infrastructure. Telephone, web, and email contacts are managed in a consistent and uniform manner whether within a single contact center or via a distributed "virtual" contact center consisting of multiple sites ranging from large call centers to regional offices to home workers. (www.netcentrex.net)    
• RADCOM Omni-Q^(TM) offers a system solution for packet voice quality management that consolidates both PSTN and packet measurements. It gives service providers and enterprises an unprecedented, network-wide view of call quality that enables them to guarantee delivery of competitive, customer-specific Service Level Agreements (SLAs). (www.radcom-inc.com)

About Sonus' OSPA

Sonus Networks' Open Services Partner Alliance Program provides a framework that offers service providers end-to-end packet-based network solutions using best-of-breed technologies and applications. The goal of the OSPA is to empower standards-based interoperability between applications, hardware vendors, and the Sonus product family. An integral part of the Sonus OSPA, the OSPA Interoperability Laboratory is the first in the industry where product interoperability is verified, trial testing is performed and complete solutions are ultimately produced. To find additional information on the OSPA, including a list of all OSPA partners, log on to http://ospa.sonusnet.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 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 Sonus' Quarterly Report on Form 10-Q, dated November 14, 2001, 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 Company's ability to grow its customer base, dependence on new product offerings, market acceptance of its products, integration risks relative to its acquisition of telecom technologies, rapid technological and market change and manufacturing and sourcing risks.

Open Services Partner Alliance is a service mark of Sonus Networks and Open Services Architecture is a trademark of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated.