WESTFORD, Mass., December 28, 2007 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider IP-voice infrastructure solutions, today announced it will participate in the following investor conference. The live webcast will be available to the public at http://www.sonusnet.com/contents/corporate/investorrelations.cfm and the replays will be archived on the Sonus Networks website.

Citi's 18th Annual Entertainment, Media and Telecommunications Conference
Phoenix, AZ
Wednesday, January 9, 2008 at 9:45 am MST
Speaker: Hassan Ahmed, President, Chairman and CEO

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 Westford, Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

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.