E.5 3GPP HNB Procedures – CS Support

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

E.5.1 S9a CS Session Establishment

In the following procedure, the PCRF is the V-PCRF for the roaming UE.

Figure E.5.1.1: S9a CS session Establishment

1. The HNB GW receives a trigger to establish an S15 session with the PCRF when the HNB performs the registration to the HNB GW.

2. The HNB GW initiates an S15 session with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value INITIAL_REQUEST. The HNB GW provides the HNB Local IP address and the UDP source port number of IPSec tunnel if NA(P)T is detected.

3. The PCRF stores the information received in the CCR.

4. The PCRF acknowledges the session establishment by sending a CCA message.

5. The PCRF shall send a TER command to BPCF to trigger an S9a session establishment procedure. The PCRF provides HNB Local IP address and UDP source port number if available. The PCRF shall include the Auth-Session-State AVP set to NO_STATE_MAINTAINED.

NOTE: When the HNB performs the registration to the HNB GW, there is no PS service handled by the HNB. So there is no already established S9a session for the HNB.

6. The BPCF acknowledges the TER command by sending a TEA command.

7. The BPCF initiates an S9a session establishment with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value INITIAL_REQUEST. The BPCF provides HNB local IP address and UDP source port number if available.

8. The PCRF acknowledges the S9a Session establishment by sending a CCA to the BPCF.

E.5.2 PCRF initiated S9a CS Session Modification

In the following procedure, the PCRF is the V-PCRF for the roaming UE.

Figure E.5.2.1: S9a CS session Modification

This procedure is performed when the first UE or a subsequent UE connected to a HNB requesting a CS service.

1. The HNB GW receives RAB assignment message to request the resource for the CS service.

2. The HNB GW initiates an S15 session modification with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value UPDATE_REQUEST. The HNB GW provides QoS information derived from the RAB assignment message by the HNB GW.

3. The PCRF initiates an S9a session modification procedure to the BPCF by sending a RAR to the BPCF. The PCRF provides QoS rule generated by the PCRF based on the QoS information received in step 2.

4. Fixed Broadband access network performs the admission control based on the QoS rule received in step3 and responds with the outcome of the admission control by sending a RAA to the PCRF.

5. The PCRF responds with outcome of the admission control to the HNB GW by sending a CCA.

6. The HNB GW complete the procedure for the CS service.

E.5.2a BPCF initiated S9a CS Session Modification

In the following procedure, the PCRF is the V-PCRF for the roaming UE.

Figure E.5.2a.1: S9a CS session Modification

This procedure is performed when the first UE or a subsequent UE is connected to a HNB requesting a CS service.

1. The BPCF receives the report of the QoS rule failure

2. The BPCF initiates an S9a session modification with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value UPDATE_REQUEST. The BPCF includes QoS-Rule-Report AVP to identify the QoS rules that failed and PCC-Rule-Status AVP set to the value “INACTIVE”.

3. The PCRF acknowledges to the BPCF by sending a CCA.

4. The PCRF initiates the S15 session modification procedure by sending a RAR command to the HNB GW and includes the information as defined in clause E.5.3.2.2 of 3GPP TS 29.212 [9].

5. The HNB GW acknowledges to the PCRF by sending a RAA.

6. The HNB GW completes the procedure for the CS service.

E.5.3 S9a CS Session Termination

In the following procedure, the PCRF is the V-PCRF for the roaming UE.

Figure E.5.3.1: S9a CS Session Termination

1. The HNB GW initiates deregistration for the HNB or receives a deregistration request from the HNB.

2. The HNB GW initiates an S15 session termination with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value TERMINATION _REQUEST.

3. The PCRF acknowledges the session termination by sending a Diameter CCA message to HNB GW.

4. The PCRF sends a Diameter RAR message to the BPCF including a Session-Release-Cause AVP to indicate request for terminating the S9a session.

NOTE: When the HNB is deregistered, there is no PS service which can be handled by the HNB any more. So S9a session for the HNB can be terminated.

5. The BPCF acknowledges the S9a session termination request by sending a Diameter RAA message.

6. The BPCF initiates the S9a session termination with the PCRF by sending a CCR to the PCRF with the CC-Request-Type AVP set to the value TERMINATION _REQUEST.

7. The PCRF acknowledges the session termination by sending a Diameter CCA message to BPCF.