What type of messages does IGMP snooping listen for to restrict traffic?

IGMP snooping specifically listens for IGMP query messages to manage multicast traffic more efficiently within a network. IGMP, which stands for Internet Group Management Protocol, is used by hosts and adjacent multicast routers to establish multicast group memberships. When a device (like a switch with IGMP snooping capability) detects IGMP query messages, it learns which devices are interested in receiving specific multicast traffic. This allows the switch to restrict multicast traffic to only those ports that have requested it, helping to reduce unnecessary data flooding on the network. By focusing on IGMP queries, the switch gathers information about active multicast group memberships, effectively optimizing bandwidth usage and enhancing network performance.