Feature Description

The Packet Data Network (PDN) creation, modification, and release feature enable AMF to implement the following UDM services:

  • Initiates the P-CSCF restoration procedure

  • Sends a network-triggered PDU Session Update for IMS PDU sessions with the reactivation indication. Based on the indication, SMF takes the appropriate action on the PDU.

    During the UDM registration, the AMF sends the callback URL for the P-CSCF restoration and service name. The AMF handles the notification triggered for the Nudm_UECM_PCscfRestoration service operation received on the URI. This notification contains information about the restoration status as a failure or success.

  • Selects a combined instance of SMF and PGW-C, if the UE sends a request to establish a PDU Session with a DNN and S-NSSAI when the following conditions are true:

    • The UE MM Core Network Capability indicates that the UE supports EPC NAS.

    • (Optional) The UE subscription symbolizes support for interworking with EPS for the specified DNN and S-NSSAI of the HPLMN.

      Note

      If the conditions are not met, the AMF selects a standalone instance of SMF.