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SUPERCOMM 2001 BOOTH #2312

Partners Receive "Powered" Status upon Proven Interoperability with Sonus Products

WESTFORD, Mass., June 4, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that 17 members of its Open Services Partner Alliance^(TM) (OSPA) have demonstrated interoperability with Sonus solutions and have attained the "Powered" partner designation. The OSPA provides a framework for the development of converged network solutions for the carrier market based on Sonus' Open Services Architecture (OSA). The "Powered" partners that have completed integration testing with Sonus products include Acterna, ADTech, alexis communications, AudioCodes, congruency, HearMe, Indigo Software, ipVerse, iTelco Communications, Luminous Networks, MasterMind Technologies, NexTone Communications, Occam Networks, Riverstone Networks, Vpacket Communications, TGF Linux Communications and XACCT Technologies.  

"We have greatly enhanced our partner program today with the addition of more than two dozen products that integrate with Sonus solutions in a laboratory setting," said Terri Griffin, vice president of marketing programs, Sonus Networks. "Interoperability testing is an ongoing priority at Sonus. Through joint efforts with our partners, we will continue to offer customers end-to-end solutions that work together before ever entering the packet voice network."

Sonus' OSPA Interoperability Lab is uniquely positioned to test packet voice solutions through the use of state-of-the-art equipment within environmentally controlled facilities. Here, Sonus products are tested with partner products to produce packet voice solutions that can be quickly integrated and deployed in next generation networks. The types of products tested include softswitches, media gateways, service creation and delivery systems, and voice and data applications.

The most recent products to earn the OSPA "Powered" designation include:

• Acterna's NetOptimize Capacity Manager is a performance management application that provides vendor independent sizing, forecasting, and monitoring of the network switching fabric. Capacity Manager enables normalized network quality engineering, reliable network performance, and network resource optimization, leading to reduced network blockage and maximized service provider profitability. (www.acterna.com)
• ADTech offers IP telephony solutions including the tipcome SI-150 IP phone, a very high-performance endpoint operating at 10/100 Mb/s. ADTech's IP phone uses a built-in Smart Card reader (patent pending), which facilitates value-added services such as on-line payment, authentication, voice encryption and management of prepaid cards. The tipcome IP Phone is available in SIP or H.323 versions. (www.adtech.be)
• alexissm Enhanced Services Platform (ESP) is an enhanced voice and messaging application that enables application service providers and Internet service providers to offer alexis features and functions to an unlimited number of subscribers. alexis ESP offers service providers a scalable, revenue-generating business solution along with the ability to stay connected to customers through a global, single-point connection. Additionally, alexis ESP provides subscribers with a unified communications solution. (www.alexis.com)
• AudioCodes Media Packs are a family of 4 to 24 port Analog VoIP gateways for connecting POTS to an IP network. The Media Pack provides standards-based voice compression (G.711, G.723.1, G.726, G.729A), echo cancellation (G.165, 168), silence suppression, fax/modem relay as well as support for: H.323v2, MGCP, MEGACO and SIP. They support dual 10/100 Base-T Ethernet, FXS and FXO ports and are manageable by SNMPv2 and Web Browser. (www.audiocodes.com)
• Congruency's CNS 3200 Enhanced Hosted Communications Platform enables carriers and enterprises to deploy highly scalable, flexible and distributed hosted IP telecommunication services, such as managed and VPN telephony, over broadband networks. In addition to traditional telephony, the CNS 3200 offers advanced services such as IP voicemail, and enhanced capabilities such as the viewing real-time Web information on screen-enabled IP telephones. congruency's i.Picasso^(TM) 6000 IP Telephone is a feature-rich IP telephone with a 5.7-inch HTML enabled full-color touch-screen to help simplify call management, personalize visual content and enhance the viewing of real time Web information. (www.congruency.com)
• HearMe^(TM) VoiceSERVER^(TM) offers service providers an advanced, scalable VoIP platform for the rapid deployment of value-added applications and communication services. VoiceSERVER delivers enhanced voice communications for PSTN, IP or wireless phones, and PCs. Based on IP standards, VoiceSERVER readily integrates with existing IP networks. (www.hearme.com)
• Indigo Software, an Internet-infrastructure company, provides a full suite of SIP-based software and development tools to meet the exacting communications industry requirements of reliability, scalability and performance, allowing service providers to transform the end user experience of integrated communications. Indigo's products include the CPL enabled Indigo SIP Proxy Server^(TM), Indigo SIP Registrar Server^(TM), Indigo SIP Location Server^(TM) and the CPL enhanced Indigo SIP User Agent^(TM). (www.indigosw.com)
• ipVerse ControlSwitch acts as an open, intelligent operating system for converged communications services that work seamlessly across both traditional and next-generation networks. By harnessing the bandwidth, performance and reliability of core packet networks, ipVerse ControlSwitch makes it possible to deploy flexible subscriber services from anywhere in the service provider's network with optimized network investment and operating costs. (www.ipverse.com)
• iTelco Communications provides a highly scalable, global IP-based enhanced communication service platform to telecom carriers, Internet service providers and mobile service providers. iTelco's Enhanced Communication Services suite comprises a variety of services including unified messaging, IP conferencing and unified communications.   (www.i-telco.com)
• Luminous Networks^(TM) PacketWave^(TM) metro optical switch enables telecommunications carriers and service providers to transport large volumes of IP data traffic, along with traditional voice traffic, throughout a metropolitan area network at a fraction of the cost of prior technologies. Additional benefits of the PacketWave platform include embedded quality of service, robust reliability, carrier-grade scalability and full support for legacy data and voice services. (www.luminous.com)
• MasterMind Technologies' MEDEA Server, as an automated user-agent, provides a scalable enhanced services platform for hosting a complete range of IP-IVR features and capabilities, including ASR and TTS, via SIP or H.323. MasterMind delivers a suite of turnkey yet extensible service solutions for the MEDEA Server, including AOS Announcement Server, EKKO Unified Communications, CERES Auto Attendant, KARON Pre-Paid and ARGOS Voice Portal, all of which can be effortlessly customized using MasterMind's award-winning, visual Service Creation Environment. (www.mastermindtechnologies.com).
• The NexTone Application Switch provides the platform for policy-based call routing and signaling interworking (SIP, H.323) needed to deploy applications in an on-net IP environment while also interoperating with the Sonus softswitch and media gateway platforms for off-net calls to and from the Public Switched Telephone Network (PSTN). The family of NexTone Application Servers, including the recently announced NexTone Presence Server, enables breakthrough applications that support the mobile behavior of today's users unlike anything that is currently available on circuit switch networks. (www.nextone.com)
• The Occam Broadband Loop Carrier (BLC) cost-effectively delivers lifeline POTS and a variety of broadband services including ADSL, G.SHDSL (Global.standard High-Bit-Rate Digital Subscriber Line), and Gigabit Ethernet, to residential and business customers from a single, converged voice and data access network. (www.occamnetworks.com)
• The Riverstone Networks RS 8000 and 8600 are high performance, all-purpose metro aggregation routers. They provide a service provisioning platform for service providers in metropolitan areas. The platform supports TDM, POS/SDH, ATM, Cable (CMTS), and Gigabit Ethernet interfaces, along with MPLS, IS-IS, OSPF and BGP-4 routing. (www.riverstonenetworks.com)
• V-Bridge^(TM) from TGF Linux Communications is an IP telephony terminal adapter connecting legacy analog telephony equipment in business to broadband networks. The V-Bridge acts as a four-line analog telephone hub with a resident Ethernet gateway connecting standard telephones, fax machines, speaker phones, and modems to an IP telephone system. (www.tgflinux.com)
• Vpacket Communications' 6100 Series VDR provides intelligent IP routing of converged voice and data packets in an access network. The 6100's features include an advanced level of QoS management, monitoring, as well as auto-provisioning, configuration and device management. The 6100 offers immediate cost savings and additional revenue opportunities for service providers. (www.vpacket.com)
• The XACCT Real-Time N2B platform includes at its core the XACCTusage engine which captures granular usage data from all network and service elements. This is accomplished in real time and from all layers of the network including routers, switches, and probes, and from service elements such as e-mail, Web, video, and application servers. The N2B dynamically synthesizes this data based on business policies and transforms the data into actionable business intelligence. (www.xacct.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 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, 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 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 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' 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.