Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); LTE; Anonymous Communication Rejection (ACR) and Communication Barring (CB) using IP Multimedia (IM) Core Network (CN) subsystem; Protocol specificat
The present document specifies the stage three@ Protocol Description of the Anonymous Communication Rejection (ACR) and Communication Barring (CB) supplementary service@ based on stage one and two of the ISDN supplementary service Anonymous Call Rejection (ACR)@ Incoming Communication Barring (ICB) and Outgoing Communication Barring (OCB). 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 ACR and CB supplementary services.