4000 Router Series IP Multicast Configuration Guide

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When MLDv2 runs on the hosts and routers, Host B can explicitly express its interest in the IPv6 multicast

data that Source 1 sends to G (denoted as (S1, G)), rather than the IPv6 multicast data that Source 2

sends to G (denoted as (S2, G)). Only IPv6 multicast data from Source 1 is delivered to Host B.

Enhancement in MLD state

A multicast router that is running MLDv2 maintains the multicast address state for each multicast address

on each attached subnet. The multicast address state consists of the following information:

• Filter mode—Router keeps tracing the Include or Exclude state.

• List of sources—Router keeps tracing the newly added or deleted IPv6 multicast source.

• Timers—Filter timers which includes the time that the router waits before switching to the Include

mode after an IPv6 multicast address times out, and the source timers for source recording.

MLD support for VPNs

MLD maintains group memberships on a per-interface base. After receiving an MLD message on an

interface, MLD processes the packet within the VPN to which the interface belongs. MLD only

communicates with other multicast protocols within the same VPN instance.

Protocols and standards

• RFC 2710, Multicast Listener Discovery (MLD) for IPv6

• RFC 3810, Multicast Listener Discovery Version 2 (MLDv2) for IPv6

MLD configuration task list

Task at a

lance

Configuring basic MLD functions

• (Required.) Enabling MLD

• (Optional.) Specifying the MLD version

• (Optional.) Configuring an interface as a static member interface

• (Optional.) Configuring an IPv6 multicast group filter

Adjusting MLD performance

(Optional.) Enabling MLD fast-leave processing

Configuring basic MLD functions

Before you configure basic MLD functions, complete the following tasks:

• Enable IPv6 forwarding and configure an IPv6 unicast routing protocol so that all devices can be

interoperable at the network layer.

• Configure IPv6 PIM.

• Determine the MLD version.

• Determine the IPv6 multicast group address and IPv6 multicast source address for static group

member configuration.