4.2.2 PCEF-Initiated

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

4.2.2.1 AF located in the HPLMN

This clause is applicable if an IP-CAN Session is being released by the PCEF and the AF is located in the HPLMN.

Figure 4.2.2.1.1 : PCEF-initiated IP-CAN Session Termination – AF located in the HPLMN

In the following procedures, the V-PCRF is included to depict the roaming scenarios. H-PCRF acts as the PCRF for non-roaming Ues.

1. The PCEF detects that the terminat ion of an IP-CAN Session or bearer is required.

2. If case 2b applies (as defined in clause 4.0), PCEF sends the Remove IP-CAN Session Request to the BBERF. If case 2a applies (as defined in clause 4.0), the request goes transparently through the BBERF. In all cases, the PCEF sends a Remove IP-CAN Session Request to remove the IP-CAN Session. The form of the Remove IP-CAN Session Request depends upon the type of the IP-CAN. It can consist of separate requests for each IP-CAN Bearer within an IP-CAN Session.

3 If case 2b applies (as defined in clause 4.0), the BBERF-initiated Gateway Control Session Termination procedure as defined in clause 4.4.4 (BBERF-Initiated Gateway Control Session Termination) is initiated.

4. The PCEF receives a response to the Remove IP-CAN Session Request.

5 – 7. Same as Steps 3~5 in figure 4.2.1.1.1.

8 – 18.Same as Steps 7~17 in figure 4.2.1.1.1.

NOTE 1: Steps 2 and 5 may be executed in parallel.

4.2.2.2 AF located in the VPLMN

This clause is applicable only for the Visited Access scenario for the case when an IP-CAN Session is being released by the PCEF and the AF is located in the VPLMN

Figure 4.2.2.2.1: PCEF-Initiated IP-CAN Session Termination – AF located in the VPLMN

If the AF resides in the VPLMN, the V‑PCRF proxies AF session signalling over S9 between the V-AF and the H‑PCRF.

1. In order to perform PCEF initiated IP-CAN Session Termination Procedures, step 1 through step 9: as specified in Figure 4.2.2.1.1: PCEF Initiated IP-CAN Session Termination – AF Located in the HPLMN are executed.

For each AF session identified in step 6 (Figure 4.2.2.1.1) as bound to the IP-CAN Session being removed, steps 2-9 are executed:

2. The H-PCRF indicates the session abort to the V-AF in VPLMN by sending an ASR to the V-PCRF.

3. The V-PCRF proxies the ASR to the V-AF.

4. The V-AF responds by sending an ASA to the V-PCRF.

5. The V-PCRF proxies the ASA to the H-PCRF.

6. The V-AF sends an STR to the V-PCRF to indicate that the session has been terminated.

7. The V-PCRF proxies the STR to the H-PCRF.

8. The H-PCRF responds by sending an STA to the V-PCRF.

9. The V-PCRF proxies the STA to the V-AF.

10. Step 14 through step 17: as specified in Figure 4.2.2.1.1: PCEF Initiated IP-CAN Session Termination – AF Located in the HPLMN are executed, as needed.

NOTE: For steps 16 and 17: the details associated with the Sp reference point are not specified in this Release. The SPR’s relation to existing subscriber databases is not specified in this Release.