Telecommunications pioneer and AT&T Fellow to Direct Sonus' Advanced Development Initiatives

CHELMSFORD, Mass., October 4, 2006 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider Voice over IP (VoIP) infrastructure solutions, announced today that Vikram Saksena has been appointed Sonus' Chief Scientist. In this role, Saksena will shape and support Sonus' advanced technology direction, guide the future development of Sonus' wireless solutions, and increase Sonus' technical focus on external audiences and government agencies. Leading Sonus' advanced development initiatives, Saksena will seek out and drive the development of promising, next-generation technology for the benefit of Sonus and its customers globally.

“Since the Company's inception, Sonus has been the driving force behind some of the industry's most groundbreaking achievements and has helped the world's communications networks realize the benefits of IP-based voice technology,” said Saksena. “I look forward to helping Sonus continue that legacy in my new role as Chief Scientist.”

Saksena has been with Sonus since 2003, most recently as Chief Architect where he was responsible for next generation technologies and service provider solutions. He has over twenty years of experience in the telecom and cable industries in senior technology positions. Prior to Sonus, he spent 16 years at AT&T building their data network services, software and network infrastructure for Frame Relay, ATM, and IP. He became an AT&T Fellow and Chief Technologist of the Data Networking Business Unit responsible for service and technology innovations around IP Quality of Service, Multi-protocol Label Switching (MPLS), and Voice over IP. After AT&T, he served as the CTO and VP of Engineering of two start-up companies, MaxComm Technologies and Narad Networks, focused on developing next generation technologies for the DSL and cable markets. Saksena has published over 100 papers and has been awarded over 15 patents. He holds a Ph.D. degree in Electrical Engineering from the University of Illinois at Urbana-Champaign. He is a Senior Member of the IEEE.

“This is an exciting announcement for both Sonus and the industry at large. Vikram is one of the great innovators in the telecom industry, and has been an invaluable thought leader at Sonus,” said Hassan Ahmed, chairman and CEO, Sonus Networks. “In this new position, Vikram will further Sonus' advanced development initiatives that have helped to define Sonus as one of the most innovative and inspired telecommunication companies in the world.”

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' Quarterly Report on Form 10-Q, dated May 8, 2006, filed with the Securities and Exchange Commission, which identifies 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 and uncertainties associated with the Company's announced review of its historical stock option grants and accounting, including any potential impact of the Company's financial statements or results, the Company's inability to timely report with the Securities and Exchange Commission, the Company's potential inability to meet NASDAQ requirements for continued listing, potential investigations 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 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. All other company and product names may be trademarks of the respective companies with which they are associated.