6.3.2 Updates to procedures specified in TS 23.203 [3]
23.2143GPPArchitecture enhancements for control and user plane separation of EPC nodesRelease 17TS
6.3.2.1 IP-CAN session establishment
This clause defines interactions between the CP and UP function during the following procedures:
– IP-CAN session establishment (clause 7.2 of TS 23.203 [3])
During the above procedures following is the nature of interactions between the CP and UP function:
– The new TDF-C selects a new TDF-U and creates Sx session.
– The TDF-C modifies the TDF-U to update Sx parameters.
Figure 6.3.2.1-1: Interaction between CP and UP function with IP-CAN session establishment
1. Procedure as listed in this step is initiated as specified in the relevant clauses of this specification. The relevant steps of the procedure as specified in the figure above are executed.
2. For the solicited application reporting, the PCRF requests the TDF to establish the relevant session towards PCRF and provides ADC Rules to the TDF. The TDF-C selects a new TDF-U as specified in clause 5.12 and sends an Sx Session Establishment Request to the TDF-U to establish the Sx session.
3. The TDF-U sends an Sx Session Establishment Response to the TDF-C confirming the successful creation of the Sx session.
4. The relevant steps of the procedure as specified in the figure above are executed.
6.3.2.2 IP-CAN session termination
This clause defines interactions between the CP and UP function during the following procedures:
– IP-CAN session termination (clause 7.3 of TS 23.203 [3]).
During the above procedures following is the nature of interactions between the CP and UP function:
– The TDF-C releases the existing Sx session from the TDF-U.
Figure 6.3.2.2-1: Interaction between CP and UP function with IP-CAN session termination
1. Procedure as listed in this step is initiated as specified in the relevant clauses of this specification. The relevant steps of the procedure as specified in the figure above are executed.
2. If there is an active Sd session between TDF and PCRF, TDF-C sends an Sx Session Termination Request to the TDF-U to release the Sx session.
3. The TDF-U sends an Sx Session Termination Response to the TDF-C confirming the release of the Sx session
4. The relevant steps of the procedure as specified in the figure above are executed.
6.3.2.3 IP-CAN session modification
This clause defines interactions between the CP and UP function during the following procedures:
– IP-CAN session modification (clause 7.4 of TS 23.203 [3]).
During the above procedures following is the nature of interactions between the CP and UP function:
– The TDF-C modifies the TDF-U to update Sx parameters.
– The PGW-C modifies the PGW-U to update Sx parameters.
Figure 6.3.2.3: Interaction between CP and UP function with IP-CAN session modification
1. Procedure as listed in this step is initiated as specified in the relevant clauses of this specification. The relevant steps of the procedure as specified in the figure above are executed.
2. For the TDF solicited application reporting, and PCRF provides new ADC decisions to the TDF, TDF-C sends an Sx Session Modification Request to the TDF-U to update Sx parameters.
3. The TDF-U sends an Sx Session Modification Response to the TDF-C confirming update of Sx session.
4. The relevant steps of the procedure as specified in the figure above are executed.
5. PCRF provides the updated PCC rules, and PGW-C may send an Sx Session Modification Request to the PGW-U to update Sx parameters.
6. The PGW-U sends an Sx Session Modification Response to the PGW-C confirming the update of Sx session.
7. The relevant steps of the procedure as specified in the figure above are executed.
NOTE: If PCEF determines to trigger the procedures defined in TS 23.401 [2], e.g. modify bearer request, steps 5 and 6 are combined with the Sx Session Modification in the corresponding call flows described in clause 6.3.1.7.
6.3.2.4 Management of PFDs
This clause defines interactions between the CP and UP function during the following procedures:
– Procedures for management of PFDs (clause 7.12 of TS 23.203 [3]).
During the above procedures following is the nature of interactions between the CP and UP function:
– The PGW-C/TDF-C provision/update/remove the PFD (s) to the PGW-U/TDF-U.
Figure 6.3.2.4-1: Interaction between CP and UP function with PFD management
1. Procedure as listed in this step is initiated as specified in the relevant clauses of this specification. The relevant steps of the procedure as specified in the figure above are executed.
2. When there’s any change to the PFD (s) due to pull mode or push mode procedure, the PGW-C/TDF-C sends PFD management request to the PGW-U/TDF-U to provision/update/remove the PFD (s).
3. PGW-U/TDF-U acknowledges by responding with PFD management response message.