Netgear M4100-24G-POE+ (GSM7224P) - ProSAFE Gigabit L2+ Managed Switch Administrator's Guide
MLD Snooping
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ProSAFE M4100 Managed Switches
Multicast Listener Discovery Concepts
Multicast Listener Discovery (MLD) protocol enables IPv6 routers to discover multicast
listeners, the nodes that are configured to receive multicast data packets, on its directly
attached interfaces. The protocol specifically discovers which multicast addresses are of
interest to its neighboring nodes and provides this information to the active multicast routing
protocol that makes decisions on the flow of multicast data packets.
listeners, the nodes that are configured to receive multicast data packets, on its directly
attached interfaces. The protocol specifically discovers which multicast addresses are of
interest to its neighboring nodes and provides this information to the active multicast routing
protocol that makes decisions on the flow of multicast data packets.
Periodically, the multicast router sends general queries requesting multicast address listener
information from systems on an attached networks. These queries are used to build and
refresh the multicast address listener state on the attached networks. In response to the
queries, multicast listeners reply with membership reports. These membership reports
specify their multicast addresses listener state and their desired set of sources with
current-state multicast address records.
information from systems on an attached networks. These queries are used to build and
refresh the multicast address listener state on the attached networks. In response to the
queries, multicast listeners reply with membership reports. These membership reports
specify their multicast addresses listener state and their desired set of sources with
current-state multicast address records.
The multicast router also processes unsolicited filter- mode-change records and
source-list-change records from systems that want to indicate interest in receiving or not
receiving traffic from particular sources.
source-list-change records from systems that want to indicate interest in receiving or not
receiving traffic from particular sources.
MLD Snooping Concepts
In IPv4, Layer 2 switches can use IGMP snooping to limit the flooding of multicast traffic by
dynamically configuring Layer 2 interfaces so that multicast traffic is forwarded to only those
interfaces associated with IP multicast address. In IPv6, MLD snooping performs a similar
function. With MLD snooping, IPv6 multicast data is selectively forwarded to a list of ports
that want to receive the data, instead of being flooded to all ports in a VLAN. This list is
constructed by snooping IPv6 multicast control packets.
dynamically configuring Layer 2 interfaces so that multicast traffic is forwarded to only those
interfaces associated with IP multicast address. In IPv6, MLD snooping performs a similar
function. With MLD snooping, IPv6 multicast data is selectively forwarded to a list of ports
that want to receive the data, instead of being flooded to all ports in a VLAN. This list is
constructed by snooping IPv6 multicast control packets.
MLD is a protocol used by IPv6 multicast routers to discover the presence of multicast
listeners (nodes configured to receive IPv6 multicast packets) on its directly attached links
and to discover which multicast packets are of interest to neighboring nodes. MLD is derived
from IGMP; MLD version 1 (MLDv1) is equivalent to IGMPv2, and MLD version 2 (MLDv2) is
equivalent to IGMPv3. MLD is a subprotocol of Internet Control Message Protocol version 6
(ICMPv6), and MLD messages are a subset of ICMPv6 messages, identified in IPv6 packets
by a preceding Next Header value of 58.
listeners (nodes configured to receive IPv6 multicast packets) on its directly attached links
and to discover which multicast packets are of interest to neighboring nodes. MLD is derived
from IGMP; MLD version 1 (MLDv1) is equivalent to IGMPv2, and MLD version 2 (MLDv2) is
equivalent to IGMPv3. MLD is a subprotocol of Internet Control Message Protocol version 6
(ICMPv6), and MLD messages are a subset of ICMPv6 messages, identified in IPv6 packets
by a preceding Next Header value of 58.
The switch can snoop on both MLDv1 and MLDv2 protocol packets and bridge IPv6 multicast
data based on destination IPv6 multicast MAC addresses. The switch can be configured to
perform MLD snooping and IGMP snooping simultaneously.
data based on destination IPv6 multicast MAC addresses. The switch can be configured to
perform MLD snooping and IGMP snooping simultaneously.