1 Scope

24.4103GPPCommunication HOLD (HOLD) PSTN/ISDN simulation servicesNGN Signalling Control ProtocolProtocol specificationRelease 8TISPANTS

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. Within the Next Generation Network (NGN) the stage 3 description is specified using the IP Multimedia Call Control Protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP).