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Q2 Revenues Grow to $6.5 Million, Up 496% From Preceding Quarter

WESTFORD, Mass., July 13, 2000  – Sonus Networks, Inc. (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today reported financial results for its second quarter ended June 30, 2000. 

Revenues for the second quarter of fiscal 2000 were $6.5 million compared with $1.1 million for the first quarter ended March 31, 2000, an increase of 496 percent. Net loss, excluding stock-based compensation, for the second quarter of fiscal 2000 was $9.0 million or $0.21 per share on a pro forma basis, compared with a net loss, excluding stock-based compensation, of $9.1 million or $0.23 per share on a pro forma basis for the first quarter of fiscal 2000. 

Net loss for the second quarter of fiscal 2000, including stock-based compensation, was $15.4 million or $0.36 per share on a pro forma basis, compared with a net loss of $16.0 million or $0.41 per share on a pro forma basis, for the first quarter of fiscal 2000. 

Revenues for the first six months of fiscal year 2000 were $7.6 million. Net loss, excluding stock-based compensation, for the first six months of fiscal year 2000 was $18.0 million or $0.44 per share, on a pro forma basis. Net loss for the first six months of fiscal year 2000 was $31.4 million or $0.77 per share on a pro forma basis.

All per share amounts above are on a pro forma basis, which assumes the conversion of all redeemable convertible preferred stock into common stock as if such conversion occurred at the date of original issuance.

"This has been a great quarter for the company across a number of fronts," said Hassan Ahmed, Sonus’ president and CEO. "Our revenue growth reflects increased customer demand for packet voice solutions, and the momentum Sonus is gaining in this fundamental and high-growth market. During the quarter, we won several new customers and our deployments with existing customers Global Crossing, Williams Communications and Intermedia continue to progress well. Additionally, with the introduction of our access strategy, Sonus is the first to offer a single voice infrastructure platform that can be used by service providers in trunking, Internet offload and access applications."

In May 2000, Sonus Networks completed its initial public offering, raising $121.7 million. "Our IPO was an important milestone for the company, our customers and our employees, as it significantly strengthened our financial position," continued Ahmed.

In the second quarter, Sonus announced relationships with four new customers: BroadBand Office, Cybertel Corporation, USA Datanet and Z-Tel Technologies. The four service providers selected Sonus’ comprehensive Packet Telephony suite, including the GSX9000 Open Services Switch, the PSX6000 SoftSwitch and the SGX2000 SS7 Signaling Gateway, as the foundation for their next-generation packet voice infrastructures. These relationships demonstrate the breadth of Sonus’ technology as it addresses the needs of the expanding market.

During this period, Sonus also unveiled its access strategy for providing Class 5 switching infrastructure and features. The combination of Sonus’ PSX6000 SoftSwitch and GSX9000 Open Services Switch will enable Sonus’ carrier customers to deliver Class 5 features to their subscribers. Additionally, the Sonus solution will also support a range of packet-based access solutions based on integrated access devices (IADs), DSL, cable, wireless and residential and access gateways. With these capabilities, Sonus will provide carriers an end-to-end solution for delivering voice in the new public network.

Also in the second quarter, Sonus achieved a milestone in its Open Services Partner Alliance (OSPA) with the addition of 11 new providers of enhanced voice and data services. Since its inception in 1999, membership in the OSPA has doubled and currently stands at 34 telecommunications companies. 

About Sonus Networks

Sonus Networks, Inc. is a leading provider of voice infrastructure products for the new public network. Sonus’ solutions enable service providers to deploy an integrated network capable of carrying both voice and data traffic, and to deliver a range of innovative, new services. The Sonus Open Services ArchitectureÔ (OSA) and award-winning Packet Telephony suite cut the time-to-market for competitive new service products, allowing carriers and third-party developers to expand marketshare and build important new revenue streams. Its highly scalable products fully interoperate with and extend the life and utility of today’s public network. Sonus embodies in its management and staff decades of experience in developing carrier-class voice, data and multimedia solutions for implementation in the world’s largest networks. Sonus, founded in 1997, is headquartered in Westford, Massachusetts. 

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 Sonus’ Prospectus dated May 24, 2000, 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 Company’s ability to grow its customer base, dependence on new product offerings, market acceptance of our products, rapid technological and market change and manufacturing and sourcing risks.

GSX9000, PSX6000, SGX2000 and Open Services Architecture are trademarks of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated.