Question: What is the primary purpose of the CAPIF-3 reference point between the API exposing function and the CAPIF core function in the context of 3GPP Northbound APIs?
Option 1: To facilitate media transfer between User Equipment (UE) and the network, ensuring efficient data exchange.
Option 2: To exercise access and policy-related control for service API communications initiated by the API invoker, including authentication, authorization, and charging.
Option 3: To manage session establishment and teardown for voice calls within the IMS (IP Multimedia Subsystem) framework.
Option 4: To optimize wireless network parameters for improved Quality of Service (QoS) in 5G RAN deployments.
Explanation: The correct answer, Option 2, accurately reflects the role of the CAPIF-3 reference point as described. It highlights key aspects such as access control, policy enforcement, authentication, authorization (including verification based on RNAA), and charging for service API invocations. This aligns with the telecom concept of securing and managing API interactions within a network, ensuring that only authorized entities can access specific services while also facilitating billing for these services. The other options are incorrect because they pertain to different aspects of telecommunications not directly related to the function of the CAPIF-3 reference point.