What is OCS?
OCS 2007 is the centerpiece of Microsoft’s unified communications strategy to bring together e-mail, instant messaging, presence, voice and video. It is a Session Initiation Protocol (SIP)-based server that routes and switches IP-based voice traffic, as well as instant messaging and Web conferencing sessions. With Microsoft’s Office Communicator client technology front-ending the server, the need for an IP-PBX is radically diminished.