Question: In a 5G System (5GS) supporting IPTV services, what is the role of the User Plane Function (UPF) when receiving IP multicast traffic from the N6 interface?
Option 1: The UPF forwards the IP multicast traffic to the Session Management Function (SMF) for further processing.
Option 2: The UPF replicates and sends the IP multicast traffic over PDU Sessions, while also managing IGMP or MLD messages as a Proxy Subscription Agent (PSA).
Option 3: The UPF drops all IP multicast traffic from the N6 interface to prevent network congestion.
Option 4: The UPF tunnels the IP multicast traffic to the Radio Access Network (RAN) for replication.
Explanation: In the context of IPTV services in a 5GS, the UPF handles IP multicast traffic by replicating it and sending it over PDU Sessions to ensure all subscribed users receive the content. As a Proxy Subscription Agent (PSA), the UPF also manages IGMP or MLD messages for multicast group membership management, ensuring efficient and reliable IPTV service delivery over the 5G network.