This strategic analysis is part of Frost & Sullivan’s continued coverage of the North American enterprise telephony marketplace, with special focus on IP telephony. Within this analysis, Frost & Sullivan has identified market drivers, restraints, provided enterprise telephony vendors with a detailed look at the competitive landscape and provided estimated revenues and revenue forecast. The total telephony market comprises of TDM Private Branch eXchange systems (PBXs), KTSs, digital and analog phones sold in conjunction with the TDM PBXs, IP PBXs, IP-enabled PBXs and IP hard and soft phones. The enterprise IP telephony market comprises of IP-enabled PBXs, IP PBXs, and IP hard and soft phones.