Question: In a distributed deployment of UAE (UAS Application Entity) servers, what is the basis for the UAE-E reference point when CAPIF (Common API Framework) is supported?
Option 1: A customized interface specific to UAS applications
Option 2: An instance of the Diameter protocol for AAA services
Option 3: A variant of the RESTful API for internal server communications
Option 4: An instance of CAPIF-2/2e reference point as per 3GPP TS 23.222
Explanation: When CAPIF (Common API Framework) is supported in a distributed UAE server setup, the interactions between these servers (defined by the UAE-E reference point) are standardized to ensure interoperability and consistency. This is achieved by basing the UAE-E reference point on an established framework, specifically the CAPIF-2/2e reference point outlined in 3GPP TS 23.222 for Northbound APIs. This ensures a unified and predictable interface for application support functions across different UAS application entity servers.