Press Release: June 20, 2000

WR Hambrecht + Co Initiates Coverage of Sonus Networks (SONS) with a Buy Rating and a Target of $150

Company revenues expected to climb 300 percent in burgeoning voice convergence marketUnique service positions Company for long-term profit

San Francisco, CA, June 20, 2000—WR Hambrecht + Co today initiated research coverage on Sonus Networks (SONS) with a buy rating and a price target of $150. WR Hambrecht + Co.’s eNetworks Infrastructure analyst Tim Savageaux cited Sonus Networks’ early leadership in the emerging voice/data convergence market and strong management team as key reasons for the rating. WR Hambrecht + Co offers all its research reports free and real-time at www.wrhambrecht.com.

"Revenues are expected to ramp sharply for Sonus over the next several quarters as next-generation voice infrastructure deployments gain critical mass in late 2000 and into 2001. We believe our revenue estimates are conservative relative to the Company’s market opportunity and competitive position," Savageaux said.

Savageaux projects Sonus’ total revenues will reach $24.1 million in 2000 and $74.5 million in 2001.

Sonus Networks is a provider of voice infrastructure products for the new public network. The Company’s products are a new generation of carrier-class switching equipment and software that enable voice services to be delivered over packet-based networks.