IPv6 Multicast
At the alpha of this chapter, multicast is alien as one of the three abode types in IPv6.
This area goes into IPv6 multicast in added detail, starting with the agnate to IGMP for IPv4:
Multicast Listener Discovery.
Multicast Listener Discovery
Multicast receivers charge acquaint their bounded subnet multicast router that they appetite to receive
multicast traffic. Hosts accomplish this signaling application a agreement accepted as Multicast Listener
Discovery, or MLD, which is based on IGMP and performs the aforementioned tasks as IGMP does in IPv4
networks. MLD additionally uses ICMPv6 letters in its operation.
In IPv6 networks, routers act as MLD queriers to actuate which hosts appetite to accept cartage for
a accurate multicast group. Hosts are receivers, including routers, that appetite to accept that
multicast traffic. MLD hosts accelerate address letters to MLD queriers to acquaint them of their desire
to accept that multicast traffic.
MLDv1 is based on IGMPv2; MLDv2 is based on IGMPv3. Like IGMP, MLDv2 is backwardcompatible
to MLDv1 hosts and allows for MLDv1-only, MLDv2-only, and networks with mixed
MLDv1 and MLDv2 hosts.
In Cisco switches, MLD concern provides the aforementioned functionality as IGMP concern for IPv4.
That is, it provides advice to the about-face about which affiliated hosts are associates of a
particular multicast accumulation so that the about-face can accomplish decisions about whether, and on which
interfaces, to acquiesce cartage for that accumulation to breeze through the switch.
Configure a router interface to statically accompany a specific multicast accumulation (in this case FF02::FE),
regardless of whether any added accumulation associates are present on this interface, as follows:
DiMaggio(config-if)# ipv6 mld join-group ff02::fe
Explicit Tracking
Explicit tracking allows a multicast router to clue the behavior of hosts aural the IPv6 network.
This affection additionally supports the fast-leave apparatus in MLDv2, which is based on the aforementioned feature
in IGMPv3. Explicit tracking is disabled by default; you can accredit it on an interface by application the
command ipv6 mld explicit-tracking access-list-name.