Question: In a 5G System utilizing the Nmbstf-distsession API for Multicast/Broadcast Service Transport Services, what protocol may be used for authorizing access to this API based on local configuration?
Option 1: TLS (Transport Layer Security) Protocol
Option 2: Diameter Protocol with extensions for 5G
Option 3: OAuth2 Protocol using the "Client Credentials" authorization grant
Option 4: SIP (Session Initiation Protocol) with security enhancements
Explanation: The correct answer is OAuth2 Protocol using the "Client Credentials" authorization grant because, as per security considerations for this API in the context of 5G System Multicast/Broadcast Services, OAuth2 is specified for authorizing access based on local configuration, utilizing the NRF as the authorization server issuing tokens to NF Service Consumers through the "Client Credentials" flow, ensuring secure service consumption without user interaction.