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Senior Executive Brings More Than 20 Years Experience in Employee Relations and Operations

WESTFORD, Mass., May 22, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, today announced that the company has named Patrick J. Moquin as its vice president, human resources. In this role, Moquin will oversee all of Sonus' human resources functions, including organizational design, recruitment, compensation, benefits and employee development, worldwide. Moquin will report directly to Sonus president and CEO, Hassan Ahmed.

"Pat brings to Sonus tremendous experience in driving creative and innovative human resource management programs for high-growth companies," said Ahmed. "Great companies are built by great people, and we have been single-minded in our commitment to attract the industry's top talent to Sonus. Under Pat's leadership, we'll continue to make Sonus a company with whom employees want to build their futures."

"Sonus has gained a reputation for excellence with its customers, partners, investors and other constituencies, and this is directly related to the tremendous experience, dedication and work ethic of Sonus' employees," commented Moquin. "I am absolutely thrilled to be joining the Sonus family, and look forward to working with the rest of the management team in continuing to build a truly world-class operation."

Moquin joins Sonus from Applied Organizational Solutions (AOS), a provider of human resource management services. As principle at AOS, he worked with public and private companies in the areas of organizational design; merger and acquisition due diligence, transition and integration; strategic planning; rightsizing; and conflict resolution. 

Prior to forming AOS in 2000, Moquin was an executive officer and vice president of human resources at Unitrode Corporation, an emerging designer and manufacturer of analog linear integrated circuits. At Unitrode, Moquin was directly involved in the company's merger and acquisition initiatives, including their merger with Texas Instruments. 

Moquin also held several senior positions at Sun Microsystems, his last role being senior director of human resources, worldwide field operations. In that capacity, he delivered global human resources services to a $5 billion sales, systems engineering and field marketing operation with 4,400 employees. While at Sun, he assisted in the creation of a subsidiary called SunExpress, where he was instrumental in the selection of the global executive team and development of the subsidiary's operating plan. In his first position at Sun, Moquin served as senior manager, human resources for U.S. field operations, where he played a critical role in the development of the company's sales and service operations in the eastern United States. 

An attorney, Moquin possesses extensive experience in labor and employment law. He was awarded his Juris Doctorate from New England School of Law and his MBA from Rivier College. He received his Bachelor of Science in Business Administration from New Hampshire College.

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 Architecture^TM (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 market share 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. Additional information on Sonus is available at http://www.sonusnet.com.

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.