TIA TIA-873.004-A

The present document defines a call control protocol for use inthe IP Multimedia (IM) Core Network (CN) subsystem based on theSession Initiation Protocol (SIP), and the associated SessionDescription Protocol (SDP). The present document is applicableto:

– the interface between the User Equipment (UE) and the CallSession Control Function (CSCF);

– the interface between the CSCF and any other CSCF;

– the interface between the CSCF and an Application Server(AS);

– the interface between the CSCF and the Media Gateway ControlFunction (MGCF);

– the interface between the S-CSCF and the Multimedia ResourceFunction Controller (MRFC);

– the interface between the CSCF and the Breakout GatewayControl Function (BGCF);

– the interface between the BGCF and the MGCF; – the interfacebetween the BGCF and any other BGCF; and

– the interface between the CSCF and an external Multimedia IPnetwork.

Where possible the present document specifies the requirementsfor this protocol by reference to specifications produced by theIETF within the scope of SIP and SDP. Where this is not possible,extensions to SIP and SDP are defined within the present document.The document has therefore been structured in order to allow bothforms of specification.

As the IM CN subsystem is designed to interwork with differentIP-Connectivity Access Networks (IP-CANs), the IP-CAN independentaspects of the IM CN subsystem are described in the main body andannex A of this specification. Aspects for connecting a UE to theIM CN subsystem through specific types of IP-CANs are documentedseparately in the annexes or in separate documents.

NOTE 1: The procedures in this document assume that ServiceBased Bearer Control (SBBC) is supported. However, it should benoted that the support for SBBC is not required in MMD.

NOTE 2: The present document covers only the usage of SIP andSDP to communicate with the entities of the IM CN subsystem. It isperfectly possible, and not precluded, to use only the capabilitiesof the IP-CAN to allow a terminal containing a SIP UA tocommunicate with SIP servers outside the IM CN subsystem, andtherefore utilise the services provided by those SIP servers. Suchusage is outside the scope of the present document.

Edition:

A

Published:

06/01/2009

Number of Pages:

310

File Size:

1 file , 5 MB