a generic session initiation framework rather than a structured method and protocol for session instantiation and control Session Description Protocol the detailed session parameters are agreed between two SIP endpoints Real Time Protocol(RTP) the actual media session is transported ◼ a generic session initiation framework rather than a structured method and protocol for session instantiation and control ◼ Session Description Protocol the detailed session parameters are agreed between two SIP endpoints ◼ Real Time Protocol (RTP) the actual media session is transported