Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; Communication HOLD (HOLD) using IP Multimedia (IM) Core Network (CN) subsystem; Protocol specification (V15.1.0; 3GPP TS 24.610 version 15
The present document specifies the stage three Protocol Description of the Communication Hold (HOLD) services@ based on stages one and two of the ISDN Hold (HOLD) supplementary services. It provides the protocol details in the IP Multimedia (IM) Core Network (CN) subsystem based on the Session Initiation Protocol (SIP) and the Session Description Protocol (SDP). The present document is applicable to User Equipment (UE) and Application Servers (AS) which are intended to support the HOLD supplementary service.