Figure 6.2.24.1 shows the message sequence chart example for indicating
"RTCP Codec Control Commands and Indications".
This procedure is identical to that of
clause 6.2.1 apart from the IMS-ALG optionally indicates that the IMS-AGW shall be prepared to receive and is allowed to send the RTCP CCM
"FIR" and/or
"TMMBR/TMMBN" feedback messages (as defined in
RFC 5104).