Sonus' Solution Enables America Online to Offer VoIP Applications, Further Enhancing the Consumer Experience

CHELMSFORD, Mass., March 08, 2005 -Sonus Networks (Nasdaq: SONS), a leading provider of voice over IP (VoIP) infrastructure solutions, today announced that America Online, Inc. has selected Sonus as a key provider for its new Internet phone service. By deploying Sonus' technology, America Online will be able to provide a suite of advanced communications features designed to put AOL® members in control of their telephone service and online communications.

"We're excited to be working with America Online, a pioneer in the evolution of the Internet, and a company that has changed the paradigm for access to information and communication services. AOL's commitment to rolling out a Sonus-powered consumer voice over broadband solution is an important step in continuing the legacy of innovation that is synonymous with both of our companies," said Hassan Ahmed, chairman and CEO, Sonus Networks.

"Sonus has collaborated closely with AOL to enable us to use VoIP as a platform to fulfill our commitment to consumers to offer the best tools to communicate and express themselves," said John McKinley, President of AOL Digital Services and Chief Technology Officer of America Online, Inc. "We can now apply our technology to change the very nature of voice calls, making them a pathway not just for conversations, but for a wide range of interactive applications."

As an industry leader in VoIP Solutions, Sonus' technology is deployed in some of the largest and most complex carrier networks around the globe. Sonus recently introduced its latest software that enables Internet Service Providers (ISPs), like America Online, to deliver advanced integrated telephony features in a web environment that significantly enhances the overall customer experience, such as SMS (simple message service) integration, click to dial and voice to email applications.

This new software release extends the voice market beyond traditional telecommunication service providers and begins to fully leverage the benefits of an all IP network. By the end of 2004, broadbandtrends.com estimates that worldwide there were over 150 million broadband subscribers and that number is expected to more than double by 2009. Sonus' solution enables ISPs to extend their offerings to this growing segment of the market and improve their customer lifetime with comprehensive services.

America Online will deploy Sonus' GSX9000TM Open Services Switch, the InsignusTM Softswitch and the Sonus InsightTM Management System in its consumer VoIP offering.

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 Open Services ArchitectureTM (OSA), Sonus delivers end-to-end solutions addressing a full range of carrier applications, including trunking and tandem switching, residential and business access, network border switching and enhanced services. Sonus' voice infrastructure solutions, including media gateways, softswitches and network management systems, are deployed in service provider networks worldwide. Sonus, founded in 1997, 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/A dated July 28, 2004 and filed with the SEC, and the "Cautionary Statements" section of Sonus' Quarterly Report on Form 10-Q, dated November 9, 2004 and filed with the SEC, which identify important risk factors that could cause actual results to differ from those contained in the forward-looking statements. In addition, 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. Open Services Architecture, GSX9000 and Insignus are trademarks of Sonus Networks. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners.