Sylantro Systems, T-Portal, and VoiceGenie Technologies 

Join Telecom Alliance That Helps Carriers Increase Service Revenue

WESTFORD, Mass., July 19, 2000 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure products for the new public network, today announced the addition of three new members to the Open Services Partner Alliance™  (OSPA).  The most recent vendors to join the Alliance include  Sylantro Systems Corporation, T-Portal, and VoiceGenie Technologies, Inc.  The Alliance is comprised of 37 companies that rapidly develop and deliver competitive services and applications based on Sonus’ Open Services ArchitectureTM (OSA). 

“We’re very pleased with the continued success of our partner program and specifically with the variety and breadth of applications developed by our Alliance members,” said Gary Rogers, Sonus’ vice president of sales and marketing.  “Today’s announcement highlights several new and unique technologies ranging from advanced telephony applications over private IP networks to innovative voice portal systems.  The wide range of applications and services offered to our customers helps them take advantage of the many emerging benefits of the new public network.”

Telecommunications companies joining the OSPA today include:

-- Sylantro has developed the industry's leading applications-enabled softswitch that provides a carrier grade service creation platform and a suite of "revenue-ready" applications that allow service providers to offer network-hosted business telephony and related applications. These applications can be offered without the need for a Class 5 switch, yet give businesses a rich alternative that replaces their PBX or Centrex services. Sylantro's wide range of applications and XML-based service creation tools allow service providers to generate new, high margin revenue streams and penetrate new markets faster than ever before.

-- T-Portal is the first Applications Telecom Service Provider (ATSP, an industry collaboration of leading manufacturers, network service companies, and Applications Service Providers that provide a suite of seamless integrated telephony applications to affiliates like ISPs and CLECs around the world. T-Portal provides access to enhanced telecom applications like clearinghouse services, unified messaging, IP fax, conferencing, and online collaboration via simple IP connections, virtually eliminating the resources, capital and time to market delays usually encountered by service providers. T-Portal is administered by ipx, Inc., a leading VoIP company.

-- VoiceGenie Technologies has developed an advanced voice portal platform that provides a convenient, personal and flexible way to access information and make transactions over the web using a conventional or wireless telephone. VoiceGenie allows users to access the Internet by telephone to retrieve content such as email, and to perform transactions on the web by using the human voice. The technology is a result of VoiceGenie's long standing relationship with AT&T Labs Research and the evolution of several advanced technologies and new trends including computer telephony, Automatic Speech Recognition (ASR), Text to Speech and the wireless Internet.

About Sylantro Systems Corp.

Sylantro Systems™ is a software company supplying the industry’s only applications-enabled softswitch. Sylantro’s “Applications Switch” offers pre-packaged, advanced business telephony applications and also serves as a service creation platform for communications applications without the need for a Class 5 switch. Sylantro’s "revenue-ready" solutions give service providers a way to offer “ASP-like” services, which render today’s Centrex and PBX offerings obsolete. Sylantro is backed by premier investors including Mayfield Fund, Vanguard Venture Partners and Accel Partners. For more information, visit the company's website at www.sylantro.com.

About T-Portal

T-Portal is the first Applications Telecom Service Provider, ATSP, an industry collaboration of leading manufacturers, network service companies, and Applications Service Providers, who provide a suite of seamless integrated telephony applications to Affiliates like ISPs and CLECs around the world.  T-Portal has been pioneered and administered by ipx, Inc., a leading VoIP company, and is focused on the rollout of enhanced telecom service to alternate service providers around the world.  The mission of T-Portal is to eliminate the technological, resource and financial barriers to the provisioning of advanced telecom services for next generation telecom companies.

About VoiceGenie Technologies Inc.

VoiceGenie Technologies Inc. (VGTI) is a voice portal infrastructure company whose technology allows users to pick up any phone and access the internet to retrieve content, including e-mail, and to perform transactions on the web simply by using their voice.  The VoiceGenie System, consisting of VoiceGenie Applications and the VG Content Server and Telephony Server, is based on the VoiceXML standard.  The technology is a direct result of VoiceGenie's long standing relationship with AT&T Labs Research and the evolution of several advanced technologies and new trends including computer telephony, Automatic Speech Recognition (ASR), Text to Speech and the wireless internet.  VGTI recently signed a $50 M (US) agreement with Lucent and has built strategic relationships with AT&T, Nuance and Intel.  For more information on VoiceGenie Technologies, visit www.voicegenie.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.  

This press release contains forward-looking statements made pursuant to the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934.  These forward-looking statements are subject to risks and uncertainties that could cause the Company's actual results to differ materially from those anticipated, including statements concerning expected financial and operating results, growth of our customer base and revenues, future customer orders and resulting benefits from our products. Those risks and uncertainties include, among others: the risk that the market does not accept our products; our lengthy and variable sales cycle; the Company's ability to develop new products and services that keep pace with technology. For a more detailed discussion of the risks and uncertainties of Sonus Networks’ business, please refer to the Company's periodic reports and registration statements filed with the Securities and Exchange Commission, including the Company's Prospectus dated May 24, 2000.

Open Services Partner Alliance and Open Services Architecture are trademarks of Sonus Networks.  All other company and product names may be trademarks of the respective companies with which they are associated.