SMF PCF Failure Handling

This section describes the working of SMF for message-level failure handling and the corresponding HTTP status code-based failure.

The SMF PCF failover supports the following messages that are initiated from the SMF.

  • PcfSmpolicycontrolCreate

  • PcfSmpolicycontrolUpdate

  • PcfSmpolicycontrolDelete

During the PDU session lifecycle, the SMF exchanges the messages at various stages with the PCF. Depending on the HTTP status code configured in the NRF failure profile, the SMF receives one of the following actions:

  • Ignore

  • Continue

  • Terminate

Relationship between SMF PCF Failover Messages and Actions

PcfSmpolicy controlCreate

PcfSmpolicy controlUpdate

PcfSmpolicy controlDelete

Ignore

Continue with locally configured/UDM-provided policy parameters.

Note

Do not contact PCF for subsequent messages.

PCF-Interaction Status: OFF

Continue with ‘currently available snapshot’ of policy parameters.

Contact PCF for subsequent messages.

PCF-Interaction Status: ON

Current failure ignored.

Session is deleted.

PCF-Interaction Status: Session deleted

Continue

Continue with locally configured/UDM-provided policy parameters.

Note

Do not contact PCF for subsequent messages.

PCF-Interaction Status: OFF

Continue with ‘currently available snapshot’ of policy parameters.

Note

Do not contact PCF for subsequent messages.

PCF-Interaction Status: OFF

Current failure ignored.

Session is deleted.

PCF-Interaction Status: Session deleted

Terminate

Terminate the session.

Terminate the session.

Terminate the session.