A.12 Resource Sharing

29.2143GPPPolicy and charging control over Rx reference pointRelease 17TS

The P-CSCF may indicate to the PCRF that media of an AF session may share resources with media belonging to other AF sessions according to 3GPP TS 23.228 [16].

If the P-CSCF determines that resource sharing is possible, it may at establishment of a new AF session, include the Sharing-Key-UL AVP and/or Sharing-Key-DL AVP indicating that media resources may be shared in the related direction. The P-CSCF shall assign a distinct value for the Sharing-Key-UL AVP and/or Sharing-Key-DL AVP for each media component identified by the Media-Component-Description AVP for the AF session.

NOTE 1: When resource sharing applies to both directions for a certain media component, the P-CSCF can assign the same value for Sharing-Key-UL AVP and Sharing-Key-DL AVP within the same media component.

The P-CSCF shall not include the Sharing-Key-UL AVP and/or Sharing-Key-DL AVP within the Media-Component-Description AVP when the AF session relates to an Emergency Session.

The PCRF shall not include the Sharing-Key-DL AVP and/or Sharing-Key-UL AVP for those PCC/QoS Rules related to the RTCP traffic.

Trigger conditions that require applying or stopping resource sharing are described in 3GPP TS 24.229 [17].

NOTE 2: When P-CSCF needs to stop sharing according to the procedures described in 3GPP TS 24.229 [17], the P-CSCF will provide new values for the Sharing-Key-UL AVP and/or Sharing-Key-DL AVP that are not being used by any other AF sessions for the same user.