WESTFORD, Mass. -- Unefon and Sonus Networks (Nasdaq: SONS) today announced that Unefon has chosen Sonus Networks to deploy a next-generation packet voice network that will support access services, long distance voice and enhanced services. Unefon will implement Sonus' Open Services Architecture(TM) (OSA) and voice infrastructure solutions, including the GSX9000(TM) Open Services Switch, the Insignus(TM) Softswitch and the Sonus Insight(TM) Management System. "Through the Sonus-based infrastructure we're announcing today, Unefon will deploy a network to service enterprise and residential customers who will be able to take advantage of the improved economics offered by voice over IP," said Juan Carlos Olvera, Unefon's director of Fixed Telecommunication Products. "More importantly, this new packet voice network will allow us to deliver an array of traditional voice services, as well as enhanced converged voice and data applications, thus being able to satisfy all of our customers' needs at very competitive prices." Initially, Unefon will deliver access services to enterprise customers via PBX (Private Branch Exchange) connectivity. In this application, Unefon will provide connectivity for business customers' existing PBXs to the packet voice network by directly linking them to Sonus' GSX9000 Open Services Switch. By connecting PBXs to the packet voice infrastructure, Unefon can offer enterprise users a variety of standard local services that they have enjoyed with circuit-based solutions, including emergency services, direct dialing, call transfer, call privacy, call screening and more. In subsequent deployment phases, Unefon plans to leverage the Sonus-based network to deliver long distance services through its existing transmission infrastructure. Additionally, with the Sonus infrastructure, Unefon can also provide a range of SIP (Session Initiation Protocol) enhanced services, such as call center, conferencing, prepaid calling and others. Unefon plans to initially deploy the Sonus solution in Mexico City. Based on the successful implementation in this city, Unefon will deploy Sonus' packet voice infrastructure solutions in other markets where it currently provides service. Sonus Networks Inc.