Mld Overview; Introduction To Mld; Mld Version; How Mldv1 Works - 3Com MSR 50 Series Configuration Manual

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MLD Overview

Introduction to MLD

MLD Version

How MLDv1 Works

MLD C
When configuring MLD, go to the following sections for information you are
interested in:
"MLD Overview" on page 1217
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"Configuring Basic Functions of MLD" on page 1224
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"Adjusting MLD Performance" on page 1226
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"Displaying and Maintaining MLD Configuration" on page 1230
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"MLD Configuration Example" on page 1230
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"Troubleshooting MLD" on page 1232
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The Multicast Listener Discovery protocol (MLD) is used by an IPv6 router to
discover the presence of multicast listeners on directly-attached subnets. Multicast
listeners are nodes wishing to receive IPv6 multicast packets.
Through MLD, the router can learn whether there are any IPv6 multicast listeners
on directly-connected subnets, put corresponding records in the database, and
maintain timers related to IPv6 multicast addresses.
Routers running MLD use an IPv6 unicast link-local address as the source address
to send MLD messages. MLD messages are Internet control message protocol for
IPv6 (ICMPv6) messages. All MLD messages are confined to the local subnet, with
a hop count of 1.
So far, two MLD versions are available:
MLDv1 (defined in RFC 2710), which is derived from IGMPv2.
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MLDv2 (defined in RFC 3810), which is derived from IGMPv3.
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All MLD versions support the Any-Source Multicast (ASM) model. In addition,
MLDv2 can be directly used to implement the Source-Specific Multicast (SSM)
model.
n
For more information about the ASM and SSM models, see
page 1088.
MLDv1 implements IPv6 multicast listener management based on the
query/response mechanism.
MLDv1 uses two types of query messages:
ONFIGURATION
"Multicast Models" on