Sonus Networks and Cantata Technology Partner to Deliver Scalable End User Services

Integration of Cantata Media Server with Sonus' Industry Leading IMS-Ready Architecture Streamlines Consumer Access to Innovative New Services

CHELMSFORD, Mass., October 24, 2006 - Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider Voice over IP (VoIP) infrastructure solutions, and Cantata Technology, one of the world's leading independent providers of enabling communications technology, announced today that the two companies have partnered to help network operators leverage the benefits of an IP Multimedia Subsystem (IMS) environment by providing a robust framework for the development and delivery of IMS-ready applications and services. Through the partnership between Sonus and Cantata, Cantata's SnowShore® IP Media Server™ has been integrated with Sonus' IMS-ready architecture to perform the Media Resource Function (MRF) and facilitate the seamless delivery of subscriber-focused services and applications that enrich the communication experience.

"The next generation of telephony is centered on enabling the integration of multiple ways of communicating," said Steve Edwards, Chief Marketing Officer. “Our partnership with Cantata empowers network operators to start moving towards an IMS application infrastructure, while delivering immediate value through enhanced services today."

By integrating Sonus' ASX™ Feature Server and IMX™ Multimedia Application Platform, key elements of Sonus' IMS-ready architecture, with Cantata's software-based SnowShore IP Media Server, the two companies can help network operators accelerate the delivery of new services to market and provide the foundation for the development and delivery of Session Initiation Protocol (SIP) and VoiceXML (vXML)-based applications through powerful scripting capabilities and multimedia processing.

“Our partnership with Sonus combines the power of their industry-leading IMS-ready architecture with Cantata's market-leading software-based media server," said Peter Vescuso, Vice President of Marketing, Cantata. “By working together to pioneer the development of next generation voice services, we're providing the tools our customers need to differentiate themselves in an increasingly competitive market and to respond to the consumer demand for communications services that are exciting and useful."

Cantata is a strategic member of Sonus' Open Services Partner Alliance (OSPA) program, the industry's largest interoperability and testing organization. The OSPA is designed to deliver added value to network operators deploying Sonus' IMS-ready network architecture.

About Cantata Technology

Cantata Technology, established in 2006 through the combination of Brooktrout Technology® and Excel Switching Corporation, provides enabling communications hardware and software that empowers the creation and delivery of anytime, anywhere IP-based communications applications. Leveraging more than 20 years of experience, Cantata offers the broadest range of products, along with a worldwide network of partners that allows service provider and enterprise customers to develop new products, introduce new services and cost-effectively transition networks to IP. Headquartered in Needham, Mass., Cantata maintains multiple locations worldwide in North America, Asia and Europe. For more information, visit http://www.cantata.com.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of voice over IP (VoIP) infrastructure solutions for wireline and wireless service providers. With its comprehensive IP Multimedia Subsystem (IMS) solution, Sonus addresses the full range of carrier applications, including residential and business voice services, wireless voice and multimedia, trunking and tandem switching, carrier interconnection and enhanced services. Sonus' voice infrastructure solutions are deployed in service provider networks worldwide. Founded in 1997, Sonus is headquartered in Chelmsford, Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

This release may contain forward-looking statements regarding future events 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' Quarterly Report on Form 10-Q, dated May 8, 2006, filed with the SEC, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. Risk factors include among others: the impact of material weaknesses in our disclosure controls and procedures and our internal control over financial reporting on our ability to report our financial results timely and accurately; the unpredictability of our quarterly financial results; risks and uncertainties associated with the Company's announced review of its historical stock option grants and accounting, including any potential impact of the Company's financial statements or results, the Company's inability to timely report with the Securities and Exchange Commission, the Company's potential inability to meet NASDAQ requirements for continued listing, potential investigations or litigation arising out of the review or any restatement; risks associated with our international expansion and growth; consolidation in the telecommunications industry; and potential costs resulting from pending securities litigation against the company. 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. All other company and product names may be trademarks of the respective companies with which they are associated.

Cantata, Cantata Technology, Brooktrout, Brooktrout Technology, SnowShore IP Media Server and the stylized logo with and without the term Cantata Technology are trademarks or registered trademarks of EAS Group, Inc., the parent company of Cantata Technology, Inc or its subsidiaries.