B.1a Subscription to Notification of Change of IP-CAN Type at IMS Registration

29.2133GPPPolicy and charging control signalling flows and Quality of Service (QoS) parameter mappingRelease 17TS

This clause covers the optional Subscription to Notifications of change in the type of IP-CAN upon an initial IMS Registration procedure.

Figure B.1.2: Subscription to Notification of change of IP-CAN Type at initial IMS Registration

1.- The user initiates an initial SIP Registration procedure.

2. The P-CSCF requests the establishment of a new Diameter Rx session with the intention to subscribe to the notification of IP-CAN Type Change. The P-CSCF sends a Diameter AAR command to the PCRF.

NOTE: It should be possible for the P-CSCF to request the subscription to notification of IMS Signalling path status and PLMN changes also in this step.

3. The PCRF performs session binding and identifies corresponding PCC Rules related to IMS Signalling.

4. The PCRF confirms the subscription to notification of change of IP-CAN type and replies with a Diameter AAA command back to the P-CSCF. The PCRF includes in the response the type of IP-CAN currently in use.

5-7. The SIP Registration procedure is completed successfully (user has been authenticated and registered within the IMS Core NW).

8. If the PCRF had not previously subscribed to the required bearer level event from the IP-CAN (i.e. IP-CAN type change and RAT type change, if applicable), then the PCRF shall do so now. The PCRF initiates procedures according to figure 4.3.1.1.1.