H3C Technologies H3C S3100V2 Series Switches - Manual (Page 67)

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MLD snooping forwards multicast data to only the receivers that require it at Layer 2. It brings the
following advantages:
• Reducing Layer 2 broadcast packets, thus saving network bandwidth.
• Enhancing the security of multicast traffic.
• Facilitating the implementation of per-host accounting.
Basic concepts in MLD snooping
MLD snooping related ports
As shown in Figure 22 , 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 22 MLD snooping related ports
Ports involved in MLD snooping, as shown in Figure 22 , are described as follows:
• Router port—A router port is a port on the Ethernet switch that leads the switch toward the Layer-3
multicast device—DR or MLD querier. In the figure, Ethernet 1/0/1 of Switch A and Ethernet 1/0/1
of Switch B are router ports. The switch registers all its local router ports in its router port list.
• Member port—A member port—also known as “IPv6 multicast group member port”—is a port on
the Ethernet switch that leads toward multicast group members. In the figure, Ethernet 1/0/2 and
Ethernet 1/0/3 of Switch A and Ethernet 1/0/2 of Switch B are member ports. The switch registers
all the member ports on the local switch in its MLD snooping forwarding table.
NOTE:
•
In this document, a router port is a router-connecting port on the switch, rather than a port on a router.
• Unless otherwise specified, router ports and member ports in this document include static and dynamic
ports.
• On an MLD snooping-enabled switch, the ports that received MLD general queries with the source
address other than 0::0 or IPv6 PIM hello messages are dynamic router ports.