The partnership underscores Sonus' plans to create an enriched portfolio of mobile solutions

WESTFORD, Mass. and BARCELONA, Spain, February 14, 2007 - Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of serviceprovider Voice over IP (VoIP) infrastructure solutions, announced todayat the 3GSM World Congress in Barcelona, Spain that it has partneredwith 3Way Networks to develop solutions to deliver voice services andmultimedia applications to mobile handsets over an end-to-end lowpowered GSM network. 3Way Networks will provide femto cells, whichenable existing and future 2G and 3G handsets to integrate with Sonus'IP Multimedia Subsystem (IMS)-based network infrastructure. Together,the two companies are working to provide network operators with acomplete Low Powered GSM (LP GSM) solution that provides new levels ofoperational efficiency with robust support for the delivery of nextgeneration voice and multimedia services.

“As thisnew market for LP GSM solutions starts to take shape, Sonus is activelylooking to leverage relationships with leading providers of cutting edgetechnology, such as 3Way networks, to help our customers stay ahead ofthe innovation curve,” said Steve Edwards, chief marketing officer,Sonus Networks. “By integrating solutions from companies like 3WayNetworks, we are helping our customers seize the opportunity created bythe release of LP GSM spectrum to improve their core business models andprovide seamless fixed-mobile converged services to the end user.”

“The marchtowards fixed mobile convergence (FMC) is beginning to gain pace inEurope,” said Simon Albury, MD, 3Way Network. “LP GSM via femto cellsoffers mobile operators a unique means of offering converged servicesthat work with existing 3G handsets, eliminating the need to deployexpensive dual-mode technologies. We are very pleased to be working withSonus to promote and encourage adoption of LP GSM solutions and believethe partnership will help to raise awareness of the value of this typeof FMC technology.”

Additionalinformation regarding Sonus' recently announced strategy for deliveringon the promise of LP GSM can be found in the press release entitled,“Sonus Networks Unveils Strategy to Help Network Operators Capitalize onLow Powered GSM Business Opportunity” issued February 13, 2007. Sonuswill be exhibiting its industry leading solutions at the 3GSM WorldCongress, one of the wireless industry's largest tradeshows, at BoothD46, Hall 2, Level 1. Additional information on the 3GSM World Congresscan be found at http://3gsmworldcongress.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, Sonusaddresses the full range of carrier applications, including residentialand business voice services, wireless voice and multimedia, trunking andtandem switching, carrier interconnection and enhanced services. Sonus'voice infrastructure solutions are deployed in service providernetworks worldwide. Founded in 1997, Sonus is headquartered in Westford,Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

About 3Way Networks

3Way Networks was founded in 2004 and has been shipping UMTS picocelland femto cell products since 2005. Last year the company shipped over$2m worth of equipment and the company is expecting a four fold increasein sales this year.

Thisrelease may contain forward-looking statements regarding future eventsthat involve risks and uncertainties. Readers are cautioned that theseforward-looking statements are only predictions and may differmaterially from actual future events or results. Readers are referred toItem 1A “Risk Factors” of Sonus' Quarterly Report on Form 10-Q datedMay 8, 2006, filed with the SEC, which identifies important risk factorsthat could cause actual results to differ from those contained in theforward-looking statements. Risk factors include among others: theimpact of material weaknesses in our disclosure controls and proceduresand our internal control over financial reporting on our ability toreport our financial results timely and accurately; the unpredictabilityof our quarterly financial results; risks and uncertainties associatedwith the Company's announced review of its historical stock optiongrants and accounting, including any potential impact on the Company'sfinancial statements or results, any tax liabilities or penalties, theCompany's inability to timely report with the Securities and ExchangeCommission, the Company's potential inability to meet NASDAQrequirements for continued listing, potential investigations, regulatoryactions 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 costsresulting from pending securities litigation against the company. Anyforward-looking statements represent Sonus' views only as of today andshould not be relied upon as representing Sonus' views as of anysubsequent date. While Sonus may elect to update forward-lookingstatements at some point, Sonus specifically disclaims any obligation todo so.

Theproduct information in this press release is for informational purposesonly and is subject to change at Sonus' sole discretion without notice.Sonus has no obligation or commitment to develop or deliver any futurerelease, upgrade, feature, enhancement or function described in thisrelease. The information is provided “AS IS,” with all faults, andwithout any warranties whatsoever, express or implied, including, butnot limited to, warranties of merchantability, performance, or fitnessfor a particular purpose.

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