One Source Networks Selects Sonus SBC and Media Gateway to Deliver IP Migration Solutions to the Enterprise Market

Sonus's Centralized Routing Cited as a Significant Advantage Over Competing Products

WESTFORD, Mass., February 22, 2011 – Sonus Networks, Inc. (Nasdaq: SONS), a market leader in next-generation IP-based network solutions , announced that One Source Networks (OSN), a facilities-based carrier-agnostic communications solutions provider, has selected and deployed the Sonus GSX9000™ high-density media gateway with NBS session border controller functionality and the Sonus PSX Centralized Routing and Policy Server™. This deployment provides OSN the ability to manage and scale their network easily and efficiently as compared to other solutions available in the market.

One Source Networks offers SIP trunks as well as hosted PBX and advanced call center services to their customers. OSN's SIP trunks are terminated at the enterprise premise in the session border controller. As such, OSN will utilize the NBS9000 ™ to perform session border controller functions for its customers' IP endpoints and as an access session border controller for the feature server that supports SIP calling functionality.

"We selected the Sonus solution for a number of reasons, but the centralized routing capabilities really set it apart from competing solutions," said Jeff Betteker, chief operating officer of One Source Networks. "Our customers are primarily large enterprises, so a solution that supports both TDM-to-IP and IP-to-IP interconnection allows us to offer them an IP migration strategy that fits their needs and their timetable. The addition of the NBS9000 to our network will enable us to grow our business to the next level."

The Sonus platform gives significant value to enterprise customers by providing both TDM-toIP and IP-to-IP session management in one highly scalable hardware form factor. By bundling the media gateway with border security that is integrated with session control, the platform allows enterprises to implement a new network architecture that includes centralized dial-plan management, enhanced call center routing, signaling interworking between any IP-PBX or ACD, advanced media services such as integrated transcoding, and complete redundancy. In addition, Sonus's platform eliminates take-back-and-transfer charges from carrier vendors and provides proven reliability.

"As a provider of network solutions to the enterprise market, One Source Networks is on the front line of the real-world IP migration challenge," said Mykola Konrad, director of enterprise solutions at Sonus Networks. "Large enterprises, like carriers, are in the process of migrating to an all IP-to-IP network, but this process will take years. That's why the market is demanding versatile solutions that ease the migration process and allow customers to implement it at their own pace."

About One Source Networks

One Source Networks (OSN) is a facilities-based, carrier-agnostic network solutions provider based in San Antonio, TX. OSN delivers and manages wide area networks for large and medium enterprise clients by providing a single sourcing channel to deliver in-region solutions from over 100 suppliers around the world. OSN also provides leading facilities-based global VoIP services for its clients across their existing private or public WAN infrastructures. The OSN network is specifically engineered to ubiquitously interoperate with top global providers, offering superior SIP services with an unmatched direct to on-net voice quality. OSN delivers all network and voice solutions to its clients under one contract, with one account and service team, on one invoice.

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:

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

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

One Source Networks
Ilissa Miller
Jaymie Scotto & Associates
+1 866-695-3629
pr@jaymiescotto.com