Overview MLD

MLD is short for Multicast Listener Discovery Protocol, used to set up and maintain the multicast group member relation between the IPv6 host and its direct neighboring multicast device.

MLD router uses the local address of the IPv6 unicast link as the source address to send the MLD packet. MLD uses ICMPv6 (Internet Control Message Protocol for IPv6) packet type. All MLD packets are limited on the local link, and the hops are 1.

MLD has two versions: MLDv1n corresponds to IGMPv2, and MLDv2 corresponds to IGMPv3.

The packet types of the IGMP protocol adopting the IP protocol number 2 are different. The MLD protocol adopts the ICMPv6 (IP protocol number is 58) packet type, including MLD query packet (type value is 130), MLDv1 report packet (type value is 131), MLDv1 leave packet (type value is 132), and MLDv2 report packet (type value is 143). The MLD protocol and IGMP protocol have different packet formats, but have the same protocol actions.