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Revenues Grow 34% Sequentially, 285% Over Previous Year; Company Achieves Quarterly Profit 

WESTFORD, Mass., October 8, 2003 – Sonus Networks, Inc. (Nasdaq: SONS), a leading provider of carrier packet voice infrastructure solutions, today reported its financial results for the third quarter ended September 30, 2003 in accordance with U.S. generally accepted accounting principles (GAAP).  

Revenues for the third quarter of fiscal 2003 were $28.6 million compared with $21.4 million for the second quarter of fiscal 2003 and $7.4 million for the third quarter of fiscal 2002. Net income for the third quarter of fiscal 2003 was $1.2 million or $0.01 per diluted share compared with a net loss for the second quarter of fiscal 2003 of $3.2 million or $0.01 per diluted share and a net loss of $21.6 million or $0.11 per diluted share for the third quarter of fiscal 2002. 

Revenues for the first nine months of fiscal 2003 were $66.0 million compared with $49.9 million in the same period last year. Net loss for the first nine months of fiscal 2003 was $6.4 million or $0.03 per diluted share compared with a net loss for the first nine months of fiscal 2002 of $55.7 million or $0.30 per diluted share.

"This was a strong quarter for Sonus Networks, our fourth consecutive quarter of revenue growth," said Hassan Ahmed, president and CEO, Sonus Networks. "Our revenues grew 34% sequentially to $28.6 million, reflecting increased market demand for packet telephony and the expanding number of customers who have adopted Sonus' solutions. We achieved an important milestone in reporting our first quarterly profit on a GAAP basis. Additionally, we bolstered our balance sheet to capitalize on the opportunity ahead, adding $126 million to our cash and marketable securities through a common stock offering in September."

In July, Sonus disclosed that Verizon Communications has deployed Sonus' voice infrastructure solutions to support Verizon's delivery of long distance services to select markets. Verizon is carrying customer traffic on its Sonus infrastructure and is now expanding its footprint to additional U.S. markets. Also in Q3, Sonus announced that Powercom, a Wisconsin-based communications provider has deployed a Sonus-based network for domestic and international long distance, toll-free calling and calling card services, with plans to deliver local voice services in the future.  

Further expanding its presence around the globe, Sonus opened an office in India. Sonus' new direct operations in Mumbai will serve the rapidly growing India telecommunications market, including next-generation carriers as well as established service providers.

During the quarter, Sonus achieved ISO 9001:2000 certification, underscoring the company's commitment to delivering high-quality next-generation packet voice solutions. Earlier this year, Sonus became the first company to receive CUE Certification, a 3-in-1-product certification service offered by TUV America for the Canadian, United States and European markets.

Sonus' market leadership was reinforced in Q3 as Sonus was once again named the market share leader in key categories such as carrier voice over IP (VoIP) gateway revenues, minutes of VoIP traffic and revenue-generating carrier ports by independent industry research firms. Synergy Research Group recognized Sonus as a top performer in its second quarter 2003 analysis of the VoIP equipment market, with 50.9% market share in high-density VoIP gateway revenues worldwide.

Finally, Sonus continued to focus on strengthening its financial position during the quarter. In September, the company completed a public offering of its common stock, adding approximately $126 million to its balance sheet.

About Sonus Networks

Sonus Networks, Inc., is a leading provider of packet voice infrastructure solutions for wireline and wireless service providers. With its Open Services Architecture(TM) (OSA), Sonus delivers end-to-end solutions addressing a full range of carrier applications, including trunking, residential access and Centrex, tandem switching, and IP voice termination, as well as enhanced services. Sonus' award-winning 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 Westford, Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

This release may contain projections or other forward-looking statements regarding future events or the future financial performance of Sonus 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 "Cautionary Statements" section of Sonus' Quarterly Report on Form 10-Q, dated August 13, 2003 and filed with the SEC, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. These risk factors include, among others, the adverse effect of recent developments in the telecommunications industry, the weakened financial position of many service providers, Sonus' ability to grow its customer base, dependence on new product offerings, market acceptance of its products, rapid technological and market change and manufacturing and sourcing risks. 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 is a trademark of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated.