1-2
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Reducing Layer 2 broadcast packets, thus saving network bandwidth.
z
Enhancing the security of multicast traffic.
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Facilitating the implementation of per-host accounting.
Basic Concepts in MLD Snooping
MLD Snooping related ports
As shown in
Figure 1-2
, Router A connects to the multicast source, MLD Snooping runs on Switch A and
Switch B, Host A and Host C are receiver hosts (namely, IPv6 multicast group members).
Figure 1-2
MLD Snooping related ports
Router A
Switch A
Switch B
GE1/0/1
GE1/0/2
GE1/0/3
GE1/0/1
GE1/0/2
Receiver
Receiver
Host A
Host B
Host C
Host D
Source
IPv6 multicast packets
Router port
Member port
Ports involved in MLD Snooping, as shown in
Figure 1-2
, are described as follows:
z
Router port: A router port is a port on the Ethernet switch that leads switch towards the Layer-3
multicast device (DR or MLD querier). In the figure, GigabitEthernet 1/0/1 of Switch A and
GigabitEthernet 1/0/1 of Switch B are router ports. The switch registers all its local router ports in its
router port list.
z
Member port: A member port (also known as IPv6 multicast group member port) is a port on the
Ethernet switch that leads towards multicast group members. In the figure, GigabitEthernet 1/0/2
and GigabitEthernet 1/0/3 of Switch A and GigabitEthernet 1/0/2 of Switch B are member ports.
The switch registers all the member ports on the local device in its MLD Snooping forwarding table.
