C.2 RTP payload Type definition
29.0073GPPGeneral requirements on interworking between the Public Land Mobile Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN)Release 17TS
The "vnd.3gpp.clearmode" RTP payload type shall have the same PDU format and contents as defined for the Clearmode RTP payload type in IETF RFC 4040 [92].
The "vnd.3gpp.clearmode" RTP payload type shall be an "audio" media type.
In addition to the optional "ptime" and "maxptime" parameters, which shall have the same meaning as specified for the Clearmode RTP payload type in IETF RFC 4040 [92], the following additional optional MIME parameter is defined:
"network-initiated-service-change":
This parameter shall be supplied for the "3G-324.M2" codec defined in 3GPP TS 23.172 [83]. It shall be omitted for the "3G-324.M" codec defined in 3GPP TS 23.172 [83]. No values shall be supplied for this parameter.