What is IGMP Snooping?
Internet Group Membership Protocol Snooping (IGMP Snooping) is a protocol that operates on switches that allows them to dynamically learn about multicast traffic. IGMP Snooping, an industry standard, does what it implies: it snoops all traffic listening for IGMP packets. Once it sees an IGMP packet, it dynamically learns what MAC address the traffic is destined for, and what MAC address the traffic comes from. Once the switch knows the MAC address, it can look up in its table on what port to send the traffic to.
