Multicast Listener Discovery (MLD) is a component of the Internet Protocol Version 6

IPv6

Internet Protocol version 6 is a version of the Internet Protocol . It is designed to succeed the Internet Protocol version 4...

 (IPv6) suite. MLD is used by IPv6 routers for discovering multicast

Multicast

In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source creating copies automatically in other network elements, such as routers, only when the topology of the network requires...

 listeners on a directly attached link, much like IGMP is used in IPv4

IPv4

Internet Protocol version 4 is the fourth revision in the development of the Internet Protocol and the first version of the protocol to be widely deployed. Together with IPv6, it is at the core of standards-based internetworking methods of the Internet...

. The protocol is embedded in ICMPv6

ICMPv6

Internet Control Message Protocol version 6 is the implementation of the Internet Control Message Protocol for Internet Protocol version 6 defined in RFC 4443...

 instead of using a separate protocol. MLDv1 is similar to IGMPv2 and MLDv2 similar to IGMPv3. The protocol is described in RFC 3810 which has been updated by RFC 4604.

Windows Vista

Windows Vista

Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...

 and later support MLDv2. FreeBSD 8 includes support for MLDv2. The Linux kernel

Linux kernel

The Linux kernel is an operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software....

has supported MLDv2 since 2.5.68.