Multicast Listener Discovery (MLD) is a component of the Internet Protocol Version 6 (IPv6) suite.
MLD is used by IPv6 routers for discovering multicast listeners on a directly attached link, much like Internet Group Management Protocol (IGMP) is used in IPv4.
The protocol is embedded in ICMPv6 instead of using a separate protocol.
MLDv1 is similar to IGMPv2[1] and MLDv2 similar to IGMPv3.
[2] The following ICMPv6 message types are used: Several operating systems support MLDv2: