A.20 QoS hint support for data channel media

29.2143GPPPolicy and charging control over Rx reference pointRelease 17TS

If the P-CSCF receives a SIP request that requires provisioning of a service information to the PCRF, the QoSHint feature is supported and an SDP attribute "a=3gpp-qos-hint" is included in one or more of the received data channel media descriptions, the P-CSCF may provide the Desired-Max-Latency AVP and/or Desired-Max-Loss AVP for each affected application media component within the Media-Component-Description AVP(s) in the AA-Request to the PCRF.

NOTE: During the first interaction with the PCRF, the P-CSCF does not know if the QoSHint feature is supported by the PCRF. In this case the P-CSCF will include the information as if supported.

Upon receiving the information from the P-CSCF and if the QoSHint feature is supported, the PCRF shall derive the QoS information as described in 3GPP TS 29.213 [9], clause 6.3.

Annex B (normative):
Flow identifiers: Format definition and examples