Feature Description
The SMF supports Absolute Session Timeout for each PDU session. With this support, the SMF can retain the PDU session resources until the absolute session timer expires.
You can configure the absolute session timeout value under the DNN profile. If you have not configured the timeout value, the session timeout feature appears disabled and no timer is initiated.
Based on the configured value under the DNN profile, the absolute session timer is triggered during the session creation. You cannot modify the timer value during interim handling of any access and mobility procedures for that session. After the timer expires, the SMF performs SMF-initiated release by informing all SBI interfaces and N4 Interfaces, that is, toward UE, UDM, PCF, CHF, and UPF interfaces.