Enables Improved Performance and Rapid Expansion of IP-Voice Networks for Burgeoning Wireless and European Markets

WESTFORD, Mass., October 31, 2007 – Sonus Networks, Inc. (Nasdaq: SONS), a leading supplier of service provider IP-voice infrastructure solutions, today unveiled new hardware modules for the GSX9000™ Open Services Switch. Capable of delivering high levels of throughput and compression in a single module, the new suite of Circuit Network Server (CNS) modules are designed to ease the transition to next-generation networks while significantly improving the operating efficiency of today's most widely-deployed IP-based networks. Building upon a decade of IP-voice innovation, Sonus is providing operators with an effective solution for extending the benefits of IP-voice throughout the network, while delivering the services that voice subscribers expect today and the agility to address future requirements.

"Sonus' leadership in the market is due to our ability to anticipate our customers' needs and deliver sophisticated solutions that address their most demanding business challenges. As the world's largest network operators look to extend the benefits and efficiencies of their IP networks by accelerating the migration of traffic onto their IP core, the demand for higher density solutions continues to increase," said Vikram Saksena, Chief Technology Officer, Sonus Networks. "It is important for Sonus to extend operators' investments, reach new scalability thresholds and provide costs-effective, non-disruptive upgrades for deployed networks. Sonus has once again surpassed these objectives with its customer-centric commitment to innovation and its new CNS modules."

Sonus remains fully committed to protecting the investment leading operators around the globe have already made in the GSX platform and the latest CNS module is just one example of how Sonus enables operators to keep pace with escalating business requirements, while controlling costs. The new suite of CNS modules is fully interoperable with Sonus' flagship GSX9000™ platform offering scalability, reliability and security, while continuing to provide superior investment protection. The new CNS modules leverage the widely deployed Sonus Insight™ Management operating system that offers operators the unique ability to seamlessly update their entire platform without service interruption.

Designed for large-scale voice networks, the GSX9000 platform can now scale to deliver up to three times the compression (or throughput) when using the new CNS modules with built in digital signal processors. These modules are NEBS-compliant, ensuring the platform continues to meet the strict set of safety, spatial and environmental design guidelines required for today's leading communications networks.

The new CNS modules feature the latest Digital Signal Processing (DSP) technology from Texas Instruments, critical functionality for wireline, wireless and MSO networks. Sonus' disciplined approach to development with the industry's leading DSPs eases operator concerns regarding interoperability and can lower operating costs, while increasing performance, particularly for network operators where bandwidth constraints are an important business driver.

In addition to providing enhanced performance for existing Sonus customers, the new modules extend Sonus' ability to address its fastest growing markets. The new CNS modules include STM-1 interfaces and three times the number of E1 telephone network interfaces in the same footprint, signaling standards that are widely relied upon by European network operators, one of Sonus' fastest growing target geographies. Network operators throughout Europe have embraced end-to-end IP solutions to provide a new generation of subscriber services and applications to consumer and enterprise users. With the number of end users continuing to scale, the demand on IP core networks continues to increase. Sonus' ability to meet this demand, particularly in networks with bandwidth constraints, further strengthens Sonus' growing position in the region.

In addition, the new CNS modules are designed to support for a broad suite of wireless codecs, enabling wireless network operators to drive greater efficiencies throughout their networks. According to iLocus Research, Sonus already leads the market in wireless core networking solutions, carrying nearly 56% of all wireless IP traffic, approximately 3x the nearest competitor. With today’s announcement, Sonus further extends its ability to build the industry’s most scalable and reliable wireless network solutions.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of IP-voice 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.

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' Quarterly Report on Form 10-Q for the period ended June 30, 2007, filed with the SEC, 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 restatement of its historical stock option granting practices and accounting including regulatory actions or litigation; 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.

The information in this press release is for informational purposes only and is subject to change at Sonus' sole discretion without notice. Sonus has no obligation or commitment to develop or deliver any future release, upgrade, feature, enhancement or function described in this release. The information is provided "AS IS," with all faults, and without any warranties whatsoever, express or implied, including, but not limited to, warranties of merchantability, performance, or fitness for a particular purpose.

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.