Question: In a Generic Authentication Architecture (GAA) scenario where a Network Application Function (NAF) does not utilize User Security Settings (USSs) and the Bootstrapping Server Function (BSF) lacks a local policy for that NAF, what is the basis used by the BSF to locate subscriber information in its local memory?
Option 1: B-TID (Bootstrapping Transaction Identifier)
Option 2: NAF ID (Network Application Function Identifier)
Option 3: GSID (Generic Bootstrapping Architecture Service Identifier)
Option 4: UE ID (User Equipment Identifier)
Explanation: In the described GAA scenario, the BSF relies on the B-TID to identify and locate the relevant subscriber information stored in its local memory. This is crucial for the BSF to proceed with deriving NAF-specific shared keys in the absence of a local policy for the requesting NAF. The B-TID serves as a transactional identifier, facilitating the linkage between the request and the corresponding subscriber data necessary for key derivation.