Sonus Networks and IP Unity Partner to Deliver Enhanced Services to Certified Consumer Voice Over Broadband (C-VoBB) Solution

Integrated Solution Offers Rapid Deployment of Feature Rich, Robust C-VoBB Service

SAN JOSE, CA, and CHELMSFORD, MA, March 14, 2006 – Today at Spring VON 2006, Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider voice over IP (VoIP) infrastructure solutions, and IP Unity, a leader in carrier-grade media servers, application servers and real-time multimedia applications for IP and TDM networks, announced that the two companies have partnered to deliver a roster of enhanced services as part of the Sonus Certified Consumer Voice over Broadband (c-VoBB) solution. Available today, the joint solution offers service providers a viable, robust, and cost-efficient approach for integrating and managing stand-alone messaging and sharing applications, while leveraging the benefits of a rich media network.

By selecting the Sonus c-VoBB solution, the first in a series of integrated IP Multimedia Subsystem (IMS)-ready solutions designed to enable the rapid deployment of next-generation services, network operators have the ability to cost-effectively introduce a full-featured consumer voice service that includes leading applications from IP Unity, such as Mereon™ Unified Messaging, Mereon Conferencing, Collaboration, Find me-Follow me, Mereon Color Ringback Tone, and Mereon Video Messaging. As part of the partnership, Sonus and IP Unity will also continue to deliver joint solutions that leverage the power and scope of Sonus' IMS-ready architecture, IP Unity's IMS-compliant Mereon Media Server, Mereon Application Server, and Mereon product suite to further enhance the services capabilities of the application layer of Sonus' industry-leading IMS solutions.

my peopleTM , LLC, a new provider of residential VoBB, is one of the first service providers to roll out the Sonus certified c-VoBB solution with IP Unity applications. my people represents a fresh approach to VoBB by focusing on its feature set, including speech-enabled dialing and content navigation, and programmable wake up and reminder messages, in addition to providing unlimited calling.

“We selected the Sonus-IP Unity solution not only because it allowed us to deliver a rich service in the shortest time to market, but also because the solution efficiently leverages one integrated platform for many diverse features, allowing us to add new services quickly and supporting a compelling path to future IMS-centered innovation,” said Alan Creighton, president and CEO for my people. “We are also offering a turn-key service through my people Wholesale to independent cable operators who want the best infrastructure available today, without having to make the necessary up-front investment.”

Essential to a successful IMS deployment is the ability for elements within the network to communicate with each other using Session Initiation Protocol (SIP). Sonus tests the SIP capabilities of vendors through its Open Services Partner Alliance (OSPA), the industry's largest VoIP interoperability program. IP Unity has been a member of the OSPA since June 2001 and is one of Sonus' Strategic Partners.

“Sonus is an excellent partner for collaboration on consumer services delivery,” said Keith Bhatia, CTO and senior vice president of business development for IP Unity. “Together we have completed all interoperability gates and significantly improved the speed and ease of platform deployment for emerging markets carriers such as my people Wholesale. Sonus has an outstanding record of winning contracts among today's most innovative service providers, and we are very pleased to provide our IMS-ready, modular Mereon 3000 Media Server and rich media services as part of the Sonus c-VoBB solution.”

“Sonus' IMS-based architecture has been embraced by some of the largest service providers across the globe, and IP Unity is one of the first enhanced services platform providers to deliver an aggressive and market-driven multiphase roadmap for IMS compliance,” said Mike Hluchyj, Founder and CTO, Sonus Networks. “By teaming together, we are able to deliver a sophisticated IMS-driven solution for next generation voice services.”

“The nature of voice communications is changing dramatically, and the ability to deliver enhanced content-driven services will be a defining feature for tomorrow's service providers,” said Teresa Mastrangelo, Principal Analyst with Broadbandtrends.com. “Anything solution providers like Sonus and IP Unity can do to make that process faster, more robust, and more dynamic will ultimately benefit their customers. Committing to close integration now is an important step to pave the way for future innovation from these two industry leaders.”

Sonus Networks is exhibiting at Spring VON 2006 at Booth #517. IP Unity is demonstrating its solutions at Booth #325.

About IP Unity

IP Unity is the leader in delivering carrier-grade media servers, application servers and real-time multimedia applications over IP, TDM and enterprise networks. The company's open and modular Mereon™ solutions let service providers; large enterprises and public institutions quickly deploy services ranging from simple personal communications to complex rich media information and enterprise services. IP Unity solutions feature carrier-class reliability and scalability, intelligent resource management and ease of customization, resulting in optimal total cost of ownership. IP Unity's comprehensive multiservice solutions are deployed across traditional and all-IP broadband, fixed, mobile and FMC networks around the world. For more information, go to www.ip-unity.com or call 408-582-1100.

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' Annual Report on Form 10-K, dated March 14, 2006, filed with the SEC, which identify 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 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, Inc. Sonus GSX9000 Open Services Switch, PSX Call Routing Server, SGX Signaling Gateway, and the Sonus Insight Management System are trademarks of Sonus Networks, Inc. All other company and product names may be trademarks of the respective companies with which they are associated.