Question: What is the primary purpose of the AAA-2 reference point between the SIP core/IMS and Diameter proxy in the context of Service Enabler Architecture Layer for Verticals (SEAL)?
Option 1: To facilitate media transfer during voice calls
Option 2: For authentication and security to the service layer, particularly during migration
Option 3: To manage Quality of Service (QoS) for vertical services
Option 4: For billing and charging data exchange between network elements
Explanation: The AAA-2 reference point is specifically utilized for handling authentication and ensuring security at the service layer, with a particular emphasis on scenarios involving migration. This aligns with the need to securely manage user identities and access during transitional phases in network architecture, underscoring its role in maintaining the integrity of the service layer within telecom networks.