Question: Upon successful authorization of an Application Function (AF) for UE Address retrieval, what action does the Network Exposure Function (NEF) take next to determine the UE's IP address information?
Option 1: The NEF directly queries the User Equipment (UE) for its current IP address.
Option 2: The NEF invokes the Nudm_UECM_Get service operation to identify the Serving and Session Management Function (SMF) for the given GPSI, DNN, and S-NSSAI.
Option 3: The NEF sends a request to the AF to provide additional subscriber information to facilitate the UE Address retrieval.
Option 4: The NEF checks the local cache for pre-stored UE IP address information before proceeding with any external queries.
Explanation: Upon successful authorization, the NEF's next step involves identifying the SMF serving the PDU session(s) for the given identifiers (GPSI, DNN, S-NSSAI). This is achieved by invoking the Nudm_UECM_Get service operation, which enables the NEF to subsequently request and obtain the SMF-allocated IPv4 address and/or IPv6 prefix for the UE.