WESTFORD, Mass. -- Sonus Networks (Nasdaq: SONS) today announced that it has been ranked the worldwide market share leader for carrier-class packet voice switching equipment for the second quarter of 2001, its fourth consecutive quarter in this position. Reports issued by industry research firms Cahners In-Stat Group, Infonetics Research and Synergy Research Group confirm Sonus' continued leadership position in a number of market segments. "The findings from Cahners, Infonetics and Synergy continue to reflect our strong momentum in the market and the growing demand for our packet voice solutions by carriers," said Terri Griffin, vice president, marketing, Sonus Networks. "We are very proud of our leading industry position and the recognition we have received by these highly respected research firms for that achievement. Paying close attention to customer needs and aggressively executing on our product development and sales strategies continue to drive our success." Data from Cahners In-Stat Group's quarterly market share report identified Sonus as the continued leader in purpose-built carrier voice over IP (VoIP) gateways, in both port shipments and revenues, as well as the leader in total voice over packet (VoP) gateway ports shipped in all product segments. The results from the second quarter report revealed Sonus' market growth over the previous quarter and confirmed its expanding lead over competitors in these categories. Sonus Networks Inc.