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InterVoice-Brite, IPeria, Pactolus and VocalData Achieve Integration with Sonus Solutions

WESTFORD, Mass., March 19, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that four members of Sonus' Open Services Partner Alliance(R) (OSPA) have recently attained the "Powered" partner designation for proven integration with Sonus products. Solutions from InterVoice-Brite, IPeria, Pactolus and VocalData have been successfully tested for interoperability with Sonus products in the company's OSPA Interoperability Lab located in Richardson, Texas. Sonus and its 22 "Powered" partners provide fully integrated, end-to-end converged network solutions, based on Sonus' Open Services Architecture^(TM) (OSA), to the worldwide carrier market.

"The goal of Sonus' newly restructured partner program is to empower standards-based interoperability between application, softswitch and hardware vendors around the world," said Terri Griffin, vice president of marketing, INtelligentIP^(TM) division, Sonus Networks. "Powered solutions help take the guesswork out of integrating and deploying next-generation networks because they are fully tested in our lab before being installed in a carrier's network. This helps carriers deploy the necessary solutions more rapidly and economically than ever before."

Sonus' OSPA Interoperability Lab is the first of its kind in the industry to accelerate the deployment of voice services by integrating softswitches, media gateways, service creation and delivery systems, and unified voice and data applications - all based on industry standards. The Lab provides state-of-the-art testing equipment to OSPA partners within environmentally controlled private rooms. Once an OSPA member demonstrates interoperability with a Sonus product, the partner becomes "Powered."

Sonus "Powered" partners comprise a subset of the OSPA. (See today's press release "Sonus Networks Broadens and Enhances Open Services Partner Alliance Program"). The four newly "Powered" OSPA partners announced today provide a wide variety of solutions that can be integrated with Sonus products:

• iVB Network Solutions, a division of Intervoice-Brite, offers Omvia Messaging, which provides comprehensive messaging services with convenient unified access to voice, fax, and e-mail messages using Web, WAP, or voice.  Advanced messaging services support consumer and business users and are available across all wireline and mobile or fixed wireless networks.     
• The IPeria ActivEdge Enhanced Communications System is an open, carrier-class software and services infrastructure which supports both PSTN and VoIP networks.  ActivEdge enables communications service providers to generate significant incremental revenue by delivering a completely new class of next-generation services.  Through its unique I-account user interface, ActivEdge delivers a wide range of services including single-point access for voicemail, email, facsimile, paging and other messaging services.      
• The Pactolus RapidFLEX^(TM) Application Server and Service Creation Environment (SCE) is an open, extensible, Unix-based software platform that delivers high value, carrier-class enhanced services to converged networks.  The RapidFLEX SCE enables service providers to create their own XML-based applications through a graphical, software component interface that can be directly deployed on a RapidFLEX Application Server.  Pactolus offers several SCE-built, pre-packaged, trunk-side services including Prepaid Calling Card, Conference Calling, and Toll Free Number services for deployment in SIP-enabled networks.     
• VocalData's Voice over IP Softswitch (VOISSTM, "voice") solution is a proven carrier class service delivery softswitch offering basic and enhanced voice services and applications, class services, business features, conferencing and unified messaging.  VOISS is an open solution that integrates with other leading VoIP product elements (IP phones and VoIP gateways).

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 100 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 iVB Network Solutions

iVB Network Solutions, a division of InterVoice-Brite, Inc., provides network service providers worldwide with speech-enabled, consumer-oriented network communication and e-business applications as well as outsourcing services. These solutions are designed to enrich the experience of users while assisting network service providers to differentiate their services, attract new subscribers, reduce churn, and boost revenue through increased application "stickiness." Services and applications such as communications portals, content portals, messaging, unified messaging and unified communication, secure m-commerce, and prepaid and post-paid calling are marketed under the brand name Omvia^(TM). In addition, iVB Network Solutions operates as a global Communications Application Service Provider (CASP), providing products and services to network and enterprise service providers with optional levels of services and significantly lowered commitment to infrastructure expenditures. For more information about iVB Network Solutions, visit our website at www.intervoice-brite.com.

About IPeria, Inc.

Founded in 1997, IPeria is the leading developer of an application server and subscriber applications that enable telecommunications service providers to attract and retain customers. Its innovative ActivEdge^(TM) Enhanced Communication System provides voice mail, unified messaging, voice e-mail and other high-value subscriber services. Service providers use the IPeria^(TM) I-account user interface of the ActivEdge system to build strong, long-term relationships with their customers by allowing customization and personalization of the services. Privately held, IPeria is headquartered in Burlington, Massachusetts. Additional information is available at http://www.iperia.com.

About Pactolus

Pactolus Communication Software, Inc., is a leading supplier of XML-based enhanced service solutions for softswitch-enabled, converged networks. Pactolus is the first company to bring sophisticated, third-party call control capabilities to SIP-based networks using XML. The Pactolus RapidFLEX Application Server and Service Creation Environment uses the power of its eXtensible Telephony Markup Language (XTML) to deliver enhanced services with the speed and flexibility seen in delivering XML-based Internet applications. Pactolus products are sold directly to carriers and through OEM channels. For more information about Pactolus visit www.pactolus.com.

About VocalData

VocalData, based in Richardson, Texas, develops and markets service delivery softswitches and enhanced services platforms that enable communications carriers to deliver advanced telephony and communications services on next generation networks (NGNs).  VocalData's Voice over IP Softswitch (VOISS^(TM)) platform is the only complete NGN solution available today for delivering telephony services: service delivery softswitch, gateway, enhanced services platforms, and IP end-points. The Company's product suite was awarded the prestigious SUPERQuest "Most Promising New Public Networks Technology" award at the SUPERCOMM show in June 2000 and in January 2001 received Internet Telephony's "Product of the Year" in 2000. For more information visit www.vocaldata.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' 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.

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.