5-2
Figure 5-2
Sub-VLAN-based IPv6 multicast VLAN
Source
Router A
MLD querier
VLAN 2
VLAN 3
VLAN 4
Switch A
Receiver
Host A
Receiver
Host B
Receiver
Host C
IPv6 Multicast packets
VLAN 2
VLAN 3
VLAN 4
VLAN 10 (IPv6 Multicast VLAN)
After the configuration, MLD snooping manages router ports in the IPv6 multicast VLAN and member
ports in the sub-VLANs. When forwarding multicast data to Switch A, Router A needs to send only one
copy of multicast traffic to Switch A in the IPv6 multicast VLAN, and Switch A distributes the traffic to
the IPv6 multicast VLAN’s sub-VLANs that contain receivers.
Port-based IPv6 multicast VLAN
As shown in
Figure 5-3
, Host A, Host B and Host C are in three different user VLANs. All the user ports
are hybrid ports. On Switch A, configure VLAN 10 as an IPv6 multicast VLAN, assign all the user ports
to this IPv6 multicast VLAN, and enable MLD Snooping in the IPv6 multicast VLAN and all the user
VLANs.
Figure 5-3
Port-based IPv6 multicast VLAN
After the configuration, upon receiving an MLD message on a user port, Switch A tags the message
with the IPv6 multicast VLAN ID and relays it to the MLD querier, so that MLD Snooping can uniformly
manage the router ports and member ports in the IPv6 multicast VLAN. When forwarding multicast
data to Switch A, Router A needs to send only one copy of multicast traffic to Switch A in the IPv6
multicast VLAN, and Switch A distributes the traffic to all the member ports in the IPv6 multicast VLAN.