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Revenues Increased to $46.8 Million, EPS of $0.04

CHELMSFORD, Mass., November 3, 2004 – Sonus Networks (Nasdaq: SONS), a leading supplier of service provider voice over IP (VoIP) infrastructure solutions, today reported its financial results for the third quarter ended September 30, 2004.

Revenues for the third quarter of fiscal 2004 were $46.8 million compared with $22.3 million for the third quarter of fiscal 2003 and $42.4 million for the second quarter of fiscal 2004. Net income for the third quarter of fiscal 2004 was $10.3 million or $0.04 per share compared with a net loss of $5.0 million or $0.02 per share for the third quarter of fiscal 2003 and net income of $4.9 million or $0.02 for the second quarter of fiscal 2004.

“During the third quarter Sonus continued its success as a leader in the rapidly expanding VoIP market,” said Hassan Ahmed, chairman and chief executive officer, Sonus Networks. “Revenue and earnings grew sequentially and we continued to build our technology and market momentum. We released new software for the trunking and access markets, expanded our customer deployments and added new talent to our company, all of which have enhanced our global market position.”

Revenues for the first nine months of fiscal 2004 were $125.7 million compared with $46.8 million in the same period last year. Net income for the first nine months of fiscal 2004 was $18.2 million or $0.07 per share compared with a net loss for the first nine months of fiscal 2003 of $22.0 million or $0.10 per share.

Building its position with service providers and carriers around the world, Sonus continues to add new customers and expand relationships with existing customers. For example, Interoute, one of Europe’s most advanced telecommunications networks, is deploying additional Sonus equipment to meet growing demand for its successful Virtual Voice Network. Further underscoring Sonus’ success with its customers, in August the company was named the market share leader in several segments of the carrier VoIP equipment market by industry research firms In-Stat/MDR and Synergy Research Group.

Sonus also continued focusing its development efforts on extending its solutions in the trunking, access, wireless and international markets. During the third quarter, Sonus introduced the latest version of its industry-leading Open Services ArchitectureTM (OSA), which offers new capabilities that help carriers reduce dependency on legacy circuit switch technologies and accelerate the transition to VoIP. In addition, Sonus delivered product enhancements in key areas such as Class 5 services, voice over broadband, network border switching, and operations and network management.

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’ 2003 Annual Report on Form 10-K, as amended by Amendment No. 1 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 August 20, 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. Risk factors include, among others, risks associated with the company’s assessment of internal control over financial reporting as required by Section 404 of the Sarbanes–Oxley Act and the risks associated with the pending securities litigation and SEC investigation. 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, Insignus and Sonus Insight are trademarks of Sonus Networks. All other trademarks, service marks, registered trademarks, or registered service marks are the property of their respective owners.