After an MMTel session with the bootstrap data channels have been established, if the IMS AS received a re-INVITE request with an SDP offer containing application data channels media descriptions (identified by
"dcmap" attribute lines containing
"stream-id" parameter set to values starting at 1000 and associated
"a=3gpp-req-app" attribute lines as specified in
TS 26.114), the IMS AS shall notify the DCSF, may trigger the reservation or update of corresponding application data channel media resources upon the instruction from the DCSF and shall send re-INVITE request with the SDP offer containing the requested application data channel and related bootstrap data channel media descriptions according to the specific data channel application use case (e.g. P2P/P2A/P2A2P), following the procedures in
TS 23.228, and
clauses 9.3.2.2.2.2 and
9.3.3.2.2.2.