e following table illustrates the SMF service operations. The SMF interfaces with the AMF, PCF, UDM, NRF, NEF, UPF, and NWDAF to provide the following services: The Nsmf_PDUSession service controls the creation, modification, and deletion of PDU sessions. The resource is handled between the SMF and AMF via CRUD operations. The created context is associated with an SM context ID in the SMF. The Nsmf_PDUSession_Create service operation is used to create a new PDU session in the SMF or associate it with an existing PDN connection (4G) in the home SMF and PDN Gateway Control (PGW-c). The Nsmf_PDUSession_Updatesery operation is used by the SMF to update an existing PDU session. The Nsmf_PDUSession_Release service operation is used by the SMF to release or disconnect an already established PDU session. The Nsmf_PDUSession_CreateSMContext, Nsmf_PDUSession_UpdateSMContext and Nsmf_PDUSession_ReleaseSMContex S services are respectively used to create, update, or release an SMF-AMF association to support the PDU session and UE context. The eNsmf_PDUSession_SMContextStatusNotify service operation is used by the SMF to notify its consumers of SM-context-related status changes - for example, whether a PDU session is released for local reasons, or handovers. Nsmf_PDUSession_StatusNotify is used by the SMF to notify PDU-session-related changes to its consumers. Service Name Service Operations Operation Consumer(s) Nsmf_PDUSession Create Request/Response V-SMF/I-SMF Update Request/Response V-SMF/I-SMF, and H-SMF Release Request/Response V-SMF/I-SMF CreateSMContext Request/Response UpdateSMContext Request/Response SMContextStatusNotify Subscribe/Notify StatusNotify Subscribe/Notify V-SMF/I-SMF ContextRequest Request/Response AMF, I-SMF, and SMF ContextPush Request/Response SendMOData Request/Response TransferMOData Request/Response V-SMF/I-SMF TransferMTData Request/Response SMF and H-SMF Nsmf_EventExposure Subscribe Subscribe/Notify NEF, AMF, and NWDAF Unsubscribe NEF, AMF, and NWDAF Notify NEF, AMF, and NWDAF AppRelocationInfo 