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SUPERCOMM Booth #21347

Sonus Delivers SMARRT Services, A Set of Integrated Packet-Based Enhanced Services; SMARRT Services Address Key Applications Including Hosted PBX, Voice VPN, Call Center and Others

ATLANTA, Ga., June 2, 2003 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today introduced the company's SMARRT ServicesTM solutions, packet-based enhanced services that enable carriers to develop new revenue streams and differentiate themselves from competitors. Through reseller arrangements with select Open Services Partner AllianceSM (OSPA) members, Sonus is now offering a suite of the industry's most compelling enhanced services. The core SMARRT Services are: SMARRT Hosted PBXTM, SMARRT MessagingTM, SMARRT Prepaid/PostpaidTM, SMARRT Call CenterTM, SMARRT ConferencingTM and SMARRT Voice VPNTM.

"Carriers want to take advantage of the flexibility and new revenue opportunities offered by packet-based, next-generation infrastructure, which has been implemented for core trunking applications for some time," said Michael O'Hara, vice president, marketing, Sonus Networks. "Until now, a major challenge for carriers rolling out enhanced services has been testing, integrating and supporting the various components. Our SMARRT Services minimize the complexity and accelerate deployment times by bringing together best-of-breed applications and infrastructure solutions into complete, integrated service offerings."

Sonus' SMARRT Services incorporate leading enhanced services applications with Sonus' Open Services ArchitectureTM (OSA) and voice infrastructure solutions. The SMARRT Services portfolio comprises:

– SMARRT Hosted PBX – Sonus' SMARRT Hosted PBX services provide standard IP Centrex functionality as well as advanced features that take advantage of next-generation networks such as find-me/follow-me and Microsoft?? Outlook integration.
– SMARRT Messaging – SMARRT Messaging offers carriers a revenue-generating voicemail system as well as advanced unified communications capabilities that integrate voice, fax and email in a single location.
– SMARRT Prepaid/Postpaid – This feature-rich service package delivers full calling card functionality. 
– SMARRT Call Center – The SMARRT Call Center service enables carriers to provide flexible, network-based multi-media contact centers to enterprise customers.
– SMARRT Conferencing – Sonus' SMARRT Conferencing provides a state-of-the-art, yet cost-effective, collaboration solution.
– SMARRT Voice VPN – SMARRT Voice VPN delivers comprehensive VPN capabilities and features over packet-based networks, reducing capital and operational costs for both the carrier and the enterprise.

With Sonus' SMARRT Services, carriers are assured that the applications and the underlying infrastructure are tightly integrated and have been thoroughly system tested. Additionally, the Sonus enhanced services offerings are managed through the Sonus InsightTM Management System and integrate with carriers' existing back office systems. Sonus also provides a single point of customer support for the solutions.

"Service providers are excited about the opportunity to implement multi-vendor packetized voice solutions but require assistance with network integration," said Danny Klein, analyst, The Yankee Group. "Therefore, they are looking for their vendors to come to them with strategic solutions that are relatively seamless in implementation. With their SMARRT Services, Sonus takes a deliberate approach to bring tightly integrated enhanced services solutions to the service provider new voice architecture."

"IP-based enhanced services such as SMARRT Services offer several technical advantages over their TDM equivalents," commented O'Hara. "IP services, which reside on the packet network can be centralized in one location for simplified implementation, provisioning and maintenance. The physical location of the service platform is transparent to the network, which is particularly beneficial for geographically distributed applications. Finally, carriers can recognize significant cost savings from not having to backhaul traffic to a central location or purchase platforms for each region."

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 the "Risk Factors" section of Sonus' Annual Report on Form 10-K, dated March 19, 2003 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. In addition, any forward-looking statements represent Sonus' views only as of today and should not be relied upon as representing Sonus' views as of any subsequent date. While Sonus may elect to update forward-looking statements at some point, Sonus specifically disclaims any obligation to do so.

Sonus is a registered trademark of Sonus Networks. SMARRT Services, SMARRT Hosted PBX, SMARRT Messaging, SMARRT Prepaid/Postpaid, SMARRT Call Center, SMARRT Conferencing, SMARRT Voice VPN, Open Services Architecture and Sonus Insight are trademarks of Sonus Networks. Open Services Partner Alliance is a service mark of Sonus Networks. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners.