3GPP Work Item description

This page contains informal descriptive text only.  See master WID page for further details.

Feature: Combinational Services

The current TR22.979 and TR 23.899 have been progressed substantially so that the specification of combining CS and IMS services can be initiated. The TR 23.899 concludes a recommended architecture solution to be specified to address the combinational requirements, identified in TR22.979 and being specified in TS22.279,  including the need for radio/terminal capability exchange.

The specification of CSI Phase 1 is needed to address the urgent market needs to make IMS services available to the end-users.  This specification will enable fast deployment scenarios for IMS services that are build on existing service such as CS calls and IMS sessions.

The objective is to elaborate on the stage 1 (based on the details identified in TR 22.979), stage 2 and appropriate CRs to current specifications addressing the details of those CSI phase 1 capabilities as identified in TR 23.899 that are already supported by the current set of specifications or require limited standardization needs. These CSI phase 1 capabilities are:

    §         Radio capability exchange;

    §         SIP based terminal capability exchange;

    §         E.164 number exchange in SIP (if it can be accomplished in time);

    §         Adding IMS session to an ongoing CS call;

    §         Adding CS speech call to an ongoing IMS session.

The capabilities shall support interoperability between different operator networks and roaming.
It is assumed that a Building Block Work Item will exist for the stage-3 specification work.

Service Aspects:
Impacts of Supplementary Services during a multimedia session should be investigated.