This strategic analysis is part of Frost & Sullivan's continued coverage of the enterprise communications technology marketplace. The study provides telephony system vendors and other industry participants with a detailed look at the enterprise telephony market and the current and shifting dynamics in the rapidly evolving IP telephony marketplace. The total telephony market comprises TDM Private Branch eXchange systems (PBXs), KTSs, IP PBXs and IP-enabled PBXs. The enterprise IP telephony market comprises of IP-enabled PBXs and IP PBXs (client-server and converged). From a qualitative discussion standpoint, this research focuses mainly on IP PBXs.