Question: What is the primary purpose of the Mz reference point in the context of Multimedia Broadcast/Multicast Service (MBMS) architecture?
Option 1: To establish a direct connection between User Equipment (UE) and the Broadcasting Multicast Service Center (BM-SC) for service authentication.
Option 2: To facilitate communication between BM-SCs in different Public Land Mobile Networks (PLMNs) for roaming users, enabling home PLMN authorization for MBMS services.
Option 3: To manage Quality of Service (QoS) parameters for MBMS bearers across multiple PLMNs to ensure consistent service quality.
Option 4: To provide a backup interface for Gmb reference point failures, ensuring continuous MBMS service availability.
Explanation: The Mz reference point is specifically designed for roaming scenarios, allowing BM-SCs in visited and home PLMNs to communicate. This enables the home PLMN to authorize MBMS services provided to its roaming users by the visited PLMN, ensuring seamless service continuity while respecting operator policies and service agreements.