New Local Policy And Call Routing Capabilities Enable Easier And More Cost Effective
Large Scale Deployments For A Wider Range Of Voice Networks

WESTFORD, Mass., August 6, 2009 – Sonus Networks, Inc. (Nasdaq: SONS), providing network transformation through IP communications technology, today announced that it has further enhanced the Sonus Network Border Switch to help its customers target key growth markets such as IP access services with voice over broadband and SIP business trunking, while expanding its IP peering capabilities.

"The access service market is evolving as network operators need to provide connections for both TDM and IP traffic on the same network device," commented Deborah Kish, Principal Analyst at Gartner. "Carriers and enterprises have the opportunity to reduce network operating costs through secure IP connections and enabling least cost routing."

The key enhancements to the Sonus Network Border Switch include:

• Easier, More Cost Effective Deployment: For more flexible implementation, the Sonus Network Border Switch can now be deployed with local policy and built-in session routing capability. This allows carriers to install the Sonus Network Border Switch more rapidly in networks with less complex routing requirements and upgrade to a centralized routing architecture using the Sonus PSX Centralized Routing Server.
• Improve Interoperability: Quickly normalize traffic flows by resolving incompatibilities between SIP peers and end points, and the carrier’s network. This increases the variety of subscriber devices that are compatible with a carrier network and reduces post implementation support costs. This capability is critical to carriers deploying IP business trunks to a wider diversity of IP-PBXs, IADs and VOIP soft clients. Connectivity enhancements are based on the SIPconnect V1.1 draft framework from the SIP Forum for improved interoperability with IP PBXs using SIP trunks.
• Automated Security: The Sonus Network Border Switch can now automate the process to identify and isolate security threats and mis-configured end points before they impact the carrier’s network or degrade customer experience. Dynamic Blacklisting minimizes operator intervention by automatically dealing with malicious activity in large scale access deployments.
• Operational Efficiency: The introduction of the Trunk Group Activator enables simplified provisioning and faster rollout to get networks into service quickly.

"Today’s access environment requires more than a simple session border control device at the network edge," commented Shailin Sehgal, vice president of product management and marketing at Sonus Networks. "The introduction of local policy management means that for the first time, the Sonus Network Border Switch will be able to act as a standalone network element with built-in call routing functionality - a key differentiator of Sonus architecture. The Sonus Network Border Switch combines security, media switching and transcoding services in a single, scalable product."

About Sonus Networks

Sonus Networks, Inc., providing network transformation through IP communications technology, is leading the evolution of communications networks to support the multi-device demands of today’s digital lifestyle. Sonus solutions and services enable fixed, mobile and cable operators to gain session awareness and deliver multi-media capabilities essential to adding value and expanding their customer and subscriber base. Through standards based interoperable solutions and services, Sonus extends the investments made in traditional networks by enabling operators to seamlessly migrate to next generation technology and deliver the secure, reliable, scalable and cost-effective network needed to grow their business. 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. For a discussion of the risks and uncertainties which could cause actual results to differ from those contained in the forward-looking statements, see “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2008 and Quarterly Report on Form 10-Q for the quarter ended June 30, 2009.

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:

Sonus Media Relations
Lucy Millington
978-614-8240
lmillington@sonusnet.com

Racepoint Group for Sonus
Shannon Breen/Katie Traut
781-487-4600
sonus@racepointgroup.com