Sonus Networks Chosen By Tradingcom Europe For Voice Over WIFI Network Deployment

Sonus Signs First France-Based Service Provider

CHELMSFORD, Mass., May 15, 2006 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider Voice over IP (VoIP) infrastructure solutions, announced today that Tradingcom Europe Group, Europe's leading telecommunications capacities trader, has selected a suite of IP Multimedia Subsystem (IMS)-ready architecture solutions from Sonus as the foundation for Tradingcom’s complete, end-to-end IP-based voice network. Tradingcom Europe, which primarily trades wholesale telecommunications capacity with leading incumbent and alternative carriers around the world, has deployed a Sonus-based next generation network to improve operating leverage from its wholesale business, as well as to broaden its market reach by delivering a new Voice over WiFi (VoWiFi) service.

Headquartered in Paris, France, Tradingcom Europe has deployed the GSX9000™ Open Services Switch, the PSX™ Call Routing Server, and the ASX™ Access Server. In addition, Tradingcom Europe is leveraging the Sonus Network Border Switch™ (NBS) to connect directly and securely via IP to other IP-based voice networks around the world. Sonus’ NBS provides direct IP-to-IP peering functionality in a streamlined and cost-efficient manner, helping to improve Tradingcom Europe’s fundamental operating performance.

“With IP technologies becoming more and more pervasive in the voice world, building out our IP-based voice network is a critical ingredient in our overall growth strategy,” said Arnaud Beauregard, Chairman and CEO of Tradingcom Europe.“We selected Sonus as our preferred partner because of their demonstrated history of being able to rapidly deploy some of the world’s most successful IP-based voice networks, their ability to service and support our network as we grow and scale, and their solid vision for leveraging the potential of mobile IMS-based networks such as fixed-mobile convergence (FMC) applications and services.”

In the first phase of the deployment, Tradingcom will leverage its Sonus-based infrastructure to support its long-distance wholesale business, rerouting international calls through the IP-based voice network, thereby streamlining the minutes exchange process in a more cost-efficient manner. In future phases, Tradingcom’s network will support WiFi-enabled mobile phones, allowing consumers to connect directly to the IP-based voice network, and eventually, roam between fixed and wireless environments through an FMC service.

Sonus, which currently has a regional sales and support presence throughout several countries in Western Europe, including the United Kingdom, France, Germany, and the Czech Republic, has focused on developing its sales and support presence throughout Europe to address the burgeoning market opportunity. Tradingcom Europe, which is initially deploying the Sonus-based network in Paris, France, is the first French customer to choose Sonus as its preferred partner for IP-based voice solutions.

“Sonus has a number of high profile deployments throughout a number of companies in Europe, and we’re excited that with the addition of Tradingcom Europe,” said Hassan Ahmed, chairman and CEO, Sonus Networks.“Sonus is committed to aligning its resources against the most promising market opportunities. In recent years, Europe has emerged as one of the fastest growing markets for IP-based voice, and we’re encouraged that our early efforts to build our reputation as a trusted provider of the industry’s most advanced solutions are yielding results.”

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 and Quarterly Report on Form 10-Q, dated May 8, 2006, both 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.

The information in this press release is for informational purposes only and is subject to change at Sonus’ sole discretion without notice. Sonus has no obligation or commitment to develop or deliver any future release, upgrade, feature, enhancement or function described in this release. The information is provided “AS IS,” with all faults, and without any warranties whatsoever, express or implied, including, but not limited to, warranties of merchantability, performance, or fitness for a particular purpose

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