3Com 4210G Series, Руководство по настройке, Страница: 391 / 1133

4-2
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Reducing Layer 2 broadcast packets, thus saving network bandwidth.
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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 4-2 , 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 4-2
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 4-2 , are described as follows:
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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.
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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.