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Program Helps Sonus' Carrier Customers Assemble End-to-End Voice Technology Solutions

WESTFORD, Mass., July 2, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that five companies have joined the Open Services Partner Alliance^(TM) (OSPA), further increasing the range and scope of the telecom partner initiative.

The two-year-old program provides a framework to offer Sonus' carrier customers an end-to-end spectrum of packet-based network solutions. Sonus partners with companies whose innovative products complement its market-leading technologies. The OSPA consists of more than 140 partners, who range from enhanced services applications providers and network infrastructure vendors to technology and services partners.

New entrants include BeVocal Inc. of Sunnyvale, Calif.; Brix Networks Inc. of Chelmsford, Mass.; Digiquant of Roskilde, Denmark; Kagoor Networks Inc. of San Mateo, Calif.; and Navini Networks Inc. of Plano, Texas.

"In the past two years, the OSPA has served as a catalyst for our customers, providing carriers and service providers with the most extensive and up-to-date packet voice solutions for their next-generation networks," said Terri Griffin, vice president of marketing programs at Sonus Networks. "Each company that joins brings a fresh set of skills and services to the Alliance. We look forward to working with each of these new partners to develop end-to-end, integrated solutions that will deliver on the promise of the new public network."

Companies joining the Sonus OSPA today offer a wide variety of enhanced services, infrastructure products and OSS solutions to carriers and service providers:

• BeVocal's mission is to extend the power of every phone by providing telecom companies with carrier-grade solutions for creating and delivering next-generation enhanced services. Using the open, standards-based BeVocal Foundation Platform, carriers can offer business and residential customers the ability to retrieve information, manage messages and conduct transactions. Developers can also build high-quality voice applications using BeVocal Cafe, ranked as the industry's top VoiceXML development environment by CT Labs. (www.bevocal.com)
• Brix Networks develops and markets carrier-class products and services that verify the quality and real-time performance of advanced, Internet-based services, such as VoIP, VPNs, hosted applications, and streaming media. Brix Networks' solutions help carriers and service providers understand the overall performance of their networks, and establish strong, trusting relationships with their customers by providing proactive, end-to-end service level agreement (SLA) verification. The company's flagship offering - the Brix System - is a seamlessly integrated hardware and software product that is the industry's first complete solution built specially to address the Internet Protocol (IP) performance management needs of carriers and service providers. (www.brixnet.com)
• Digiquant (formerly Belle Systems) is a global provider of the multi-service platform, Internet Management System (IMS). Leading service providers around the globe use IMS to deploy, manage and bill for next-generation services, including VoIP, VPN, DSL, and 2.5 and 3G Wireless. A carrier-grade, scalable solution, IMS enables service providers to be innovative and more efficient, and to reduce the time to market for new services. IMS for VoIP supports prepaid, postpaid, calling cards, wholesale, retail, SIP, and Voice VPNs. (www.digiquant.com)
• Kagoor Networks is committed to helping service providers and carriers overcome the technical and business roadblocks that have tended to inhibit the widespread, commercial deployment of VoIP services. Kagoor's patent-pending VoiceFlowTM platform is the first VoIP-aware, wire-speed, packet-processing device that can be transparently added to IP networks. VoiceFlow classifies, measures and manipulates voice traffic, giving the provider the ability to resolve infrastructure issues such as call quality, bandwidth availability, call duration and routing quality with an expected ROI of two to eight months. (www.kagoor.com)
• Navini Networks is developing infrastructure products that service providers can use to offer lower-cost, more accessible wireless broadband access to the Internet. The company's Ripwave products provide nomadic broadband access and circumvent line-of-sight issues, giving end users the ability to log on anytime, anywhere. Navini's Ripwave lowers providers' installation costs through a zero-install, plug-and-play, retail-friendly consumer device. Navini's system consists of a base station and antenna; a comprehensive element management system; and a small, sleek CPE (customer premise equipment) that quickly connects to the end user's computer. (www.navini.com)

About Sonus' OSPA

Founded on the combination of Sonus' Open Services Partner Alliance (OSPA) Program and the INIP PoweredSM Partner Program from the acquisition of telecom technologies, inc., the OSPA has gained significant industry momentum, with membership of more than 140 leading independent vendors. The OSPA 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 suite. An integral part of the Sonus OSPA, the Interoperability Laboratory in Richardson, Texas, is the first in the industry where product interoperability is verified, trial testing is performed, and complete solutions are ultimately produced. Additional information on the OSPA is available at http://ospa.sonusnet.com.

About Sonus Networks

Sonus Networks 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 Architecture (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 market share 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. 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' Annual Report on Form 10-K, dated March 28, 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, rapid technological and market change, integration risks relating to the acquisition of telecom technologies and manufacturing and sourcing risks.

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