ETSI TS 124 229-2005 数字蜂窝通信系统(第2+阶段).全球移动通信系统(UMTS).基于会话初始协议(SIP)和会话描述协议(SDP)的互联网协议(IP)多媒体呼叫控制协议.第3阶段
Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); Internet Protocol (IP) multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP); Stage 3 3