Sonus Networks, Inc., a leading supplier of service provider voice over IP (VoIP) infrastructure solutions, announced that JAPAN TELECOM Co., Ltd., ("JAPAN TELECOM"), one of Japan's largest carriers and a wholly owned subsidiary of SOFTBANK Corp., has selected Sonus' award winning architecture as the foundation for its next generation voice network. Enabling a rich set of broadband applications and services, JAPAN TELECOM's new Sonus-based network significantly expands its market opportunity by facilitating the delivering of innovative new VoIP services across Japan. By selecting Sonus, JAPAN TELECOM will also achieve greater internetworking capabilities with its parent SOFTBANK Corp and will be able to leverage a seamless migration path for future network evolution.

SOFTBANK BB Corp, subsidiary of SOFTBANK Corp began deploying Sonus' industry-leading long distance solution for its voice network in 2003. Based on the success of SOFTBANK BB's Sonus-based VoIP network, JAPAN TELECOM is now building its own packet voice network utilizing Sonus' convergence-enabling architecture. Under the terms of this agreement with JAPAN TELECOM, Sonus is providing its GSX9000 Open Services Switch, PSX Call Routing Engine, SGX Signaling Gateway, as well as the Sonus Insight Management System.

"SOFTBANK group has taken a cutting-edge approach to technology, one that has propelled it to a leadership position in the voice over broadband communications industry," said Hassan Ahmed, chairman and CEO, Sonus Networks. "Broadband voice infrastructure is undoubtedly the future of telecommunication networks. We are very pleased that SOFTBANK's newest subsidiary has turned to Sonus Networks for such a critical component of its voice network. Our infrastructure will enable JAPAN TELECOM to realize its vision of expanding its service offerings and to provide bundled voice, data and multimedia services."

JAPAN TELECOM was acquired by SOFTBANK Group in July 2004. With a nationwide fiber optic digital network, JAPAN TELECOM is one of the largest service providers in Japan. The company is also growing its substantial international business with its worldwide presence. JAPAN TELECOM provides a wide range of voice and data communications services tailored to suit all needs of corporate, small and medium size enterprises, along with consumers.

"Our corporate mission is to revolutionize lifestyle, work style and business model with our cutting-edge broadband technology. We have decided to build our VoIP network with Sonus because they have consistently proven to provide the highest levels of performance, reliability and scalability, which we require to deliver superior service to our customer," said Sadahiro Sato, Senior General Manager, Voice Network Division, JAPAN TELECOM. "As we continue to expand our subscriber base and offer more advanced services, the ability to rapidly scale and provide the highest quality level is critical to our success. We rely on Sonus Networks to not only provide us with the industry's leading VoIP infrastructure, but also to provide us with a migration path that will enable us to evolve our network to offer true convergence. Together, our companies will help define next-generation telecommunications in the world's largest VoBB market."

The Sonus Networks' VoBB solution is deployed in production networks worldwide. Recent research from broadbandtrends.com shows that global broadband penetration accelerated to 194 million subscribers at the end of 3Q05, with VoBB subscribers nearly doubling over the past year to over 19 million. Asia, especially Japan, continues to lead worldwide adoption of VoBB services with nearly 11 million subscribers at the end of 3Q05, representing 57% of the global total.