Sonus Networks to Participate in Leading VoIP Industry Events

WESTFORD, Mass., January 20, 2011 – Sonus Networks, Inc. (Nasdaq: SONS), a market leader in next-generation IP-based network solutions , today announced that it will participate in several leading telecommunications, VoIP, and IP networking events in the first quarter of 2011, including VIPeering Conference, ITEXPO East, Mobile World Congress, and CTIA.

At these events, Sonus executives and technical staff will be available to demonstrate the company's industry-leading carrier and enterprise technologies, including Session Border Controllers (SBCs), voice security, and SIP trunking solutions. Additionally, Sonus senior product managers will be featured speakers at multiple presentations and discussions.

Government sales executives and engineering staff from Sonus will be on hand to meet with attendees in Verizon booth 1532 at West 2011 in San Diego, California, from January 25 to 27, 2011.

Sonus Attendees: Government sales executives and engineering staff
Where: San Diego Convention Center
When: January 25 - 27, 2011

At the VIPeering Conference , which will be held on February 2 to February 4, 2011 in Miami, Florida, Sonus will, as a Gold Sponsor, have a significant presence that includes featured presentations on enterprise peering and unified communications.

Sonus Speaker: Ram Ramanathan, Senior Product Manager for Routing and Policy Solutions
Where: Room VIP-03
Topic: "ENUM in LNP and Interconnection and Policy Management"
When: Wednesday, February 2 at 10:00 a.m. ET

Speaker: Mykola Konrad, Director of Enterprise Solutions
Where: Room VIP-07
Topic: "Corporate and Enterprise Peering and UC - Voice, Messaging and Strategies"
When: Wednesday, February 2 at 12:05 p.m. ET

Co-located with the VIPeering Conference is TMCnet's flagship ITEXPO 2011 , which will be held on the same dates in February in Miami, Florida. Sonus will exhibit in booth 634 and Mykola Konrad will participate in the Call Center speaking track.

Sonus Speaker: Mykola Konrad, Director of Enterprise Solutions
Where: Room CC-03
Topic: "Bringing Your Contact Center into the IP Generation"
When: Friday, February 4 at 11:00 a.m. ET

Also in February, Sonus will have a hospitality suite at Mobile World Congress 2011 to be held in Barcelona, Spain from February 14 to February 17, 2011.

Sonus Attendees: Sonus executives, including recently appointed CEO, Raymond Dolan
Where: Fira de Barcelona, Barcelona, Spain
Meetings to be held in Hall 2.0, Hospitality Suite 4.2HS25
When: February 14 - 17, 2011

At the end of February, Sonus will exhibit in Booth 837 at the Enterprise Connect show at the Gaylord Palms Convention Center in Orlando, Florida from February 28 to March 3, 2011. Mykola Konrad will speak on a SIP Trunking panel during the event.

Sonus Speaker: Mykola Konrad, Director of Enterprise Solutions Where: Room Sun B Topic: SIP Trunking panel When: Monday, February 28 at 9:00 a.m. ET

In March, Sonus will be on hand in Orlando, Florida, to meet in booth MR-525 with attendees of CTIA - the International Association for the Wireless Telecommunications Industry

Sonus Attendees: Sonus technical and marketing staff
Where: Orange County Convention Center
When: March 21 - 24, 2011

About Sonus Networks

Sonus Networks, Inc. is a leader in IP networking with proven expertise in delivering secure, reliable and scalable next-generation infrastructure and subscriber solutions. With customers in over 50 countries across the globe and over a decade of experience in transforming networks to IP, Sonus has enabled service providers and enterprises to capture and retain users and generate significant ROI. Sonus products include media and signaling gateways, policy/routing servers, session border controllers and subscriber feature servers. Sonus products are supported by a global services team with experience in design, deployment and maintenance of some of the world's largest and most complex IP networks. For more information, visit 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 Item 1A "Risk Factors" of Sonus' Annual Report on Form 10-K for the year ended December 31, 2009 and all subsequent Quarterly Reports on Form 10-Q, which identify important risk factors that could cause actual results to differ from those contained in the forward-looking statements. 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, except as required by law.

Sonus is a registered trademark of Sonus Networks, Inc. All other company and product names may be trademarks of the respective companies with which they are associated.

For more information, please contact:

Aline Kaplan
alkaplan@sonusnet.com
+1 978-614-8167

Paul Roberts
sonus@daviesmurphy.com
+1 781-418-2418