Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); TISPAN; PSTN/ISDN simulation services: Anonymous Communication Rejection (ACR) and Communication Barring (CB); Protocol specification (V8.1.0; 3GPP T
The present document specifies the@ stage three@ Protocol Description of the Anonymous Communication Rejection (ACR) and Communication Barring (CB) simulation 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). 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).