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SS8 SignalingSwitch Earns Sonus "INIP Powered" Certification After Passing Interoperability Test

WESTFORD, Mass., and SAN JOSE, Calif., February 20, 2001 - Sonus Networks, (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, and SS8 Networks, Inc. a premier provider of high-density signaling and service solutions for VoIP networks, today announced that the SS8 SignalingSwitch attained "INIP PoweredSM" status upon successfully completing interoperability testing with Sonus' INtelligentIP(R) Softswitch. SS8 Networks joins a growing number of telecom companies whose products have attained the "Powered" designation from Sonus' INIP Powered Partner Program, the first in the industry to coordinate the efforts of carriers and vendors in order to speed the deployment of standards-based voice services to end users.

SS8's SignalingSwitch is a carrier-class IP Signaling Transfer Point (STP) that provides both end-to-end VoIP signaling and location services. It is a key component of SS8's signaling and service infrastructure upon which service providers can rapidly build next-generation IN services. The SS8 SignalingSwitch transparently switches signaling messages to appropriate destinations in the network such as other SignalingSwitches, soft switches, or IN application servers. By providing carriers with IP telephony services for both SIP and H.323 networks through a single integrated platform, the SS8 SignalingSwitch enables a full suite of value-added services and applications based on industry standards.

"We are delighted that the SS8 SignalingSwitch has become "Powered" by completing integration testing with the INtelligentIP Softswitch in our Richardson, Texas lab," said Terri Griffin, vice president, INIP marketing, INtelligentIP division, Sonus Networks. "By ensuring the interoperability of solutions like SS8's SignalingSwitch with our INtelligentIP Softswitch, Sonus' "INIP Powered" program helps vendors and service providers speed the delivery of new IP solutions to end users in a transparent and cost effective manner."

"We are pleased to have achieved interoperability with Sonus' IntelligentIP Softswitch - a milestone which reflects our commitment to standards-based interoperability in VoIP signaling," said Tom Kershaw, Vice President of Product Management for SS8 Networks. "Increasingly, service providers are looking for integrated network solutions with proven track records, and our relationship with an industry leader like Sonus helps us fulfill this market requirement."

The INIP Powered Partner Program, launched in 1999, is the first of its kind to accelerate the deployment of voice over multi-service networks by integrating softswitches, media gateways, service delivery and creation systems, and unified voice and data applications with Sonus' INtelligentIP Softswitch. Through the creation of interoperable environments, Sonus and its "INIP Powered" partners help carriers and service providers offer innovative services to end users more quickly and cost-effectively. Program partners who have successfully completed testing with Sonus display the "INIP Powered" logo to signify their product is interoperable with the INtelligentIP Softswitch.

About SS8 Networks

SS8 Networks (www.SS8.com) is a leading developer of Internet signaling and services solutions that enable service providers to deliver high performance data, telephony and video services over the Internet. The company's carrier-class products enable next-generation network operators to create and deploy innovative new services that transcend the PSTN. SS8 Networks has headquarters in San Jose, California, with R&D in Ottawa, Canada.

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. 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' Prospectus, dated January 12, 2001, and associated Registration Statement on Form S-4, 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.

IntelligentIP is a registered trademark of Sonus Networks. Open Services Architecture is a 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.