Operation Manual – Multicast
H3C S5500-EI Series Ethernet Switches
Chapter 5 IPv6 Multicast VLAN Configuration
5-1
Chapter 5 IPv6 Multicast VLAN Configuration
5.1 Introduction to IPv6 Multicast VLAN
As shown in
Figure 5-1
, in the traditional IPv6 multicast programs-on-demand mode,
when hosts that belong to different VLANs, Host A, Host B and Host C require IPv6
multicast programs on demand service, Router A needs to forward a separate copy of
the IPv6 multicast data in each VLAN. This results in not only waste of network
bandwidth but also extra burden on the Layer 3 device.
IPv6 multicast packet transmission
without IPv6 multicast VLAN
Source
Router A
IPv6 multicast packets
IPv6 multicast packet transmission
when IPv6 multicast VLAN runs
Source
Router A
Switch A
Host A
Receiver
Host B
Receiver
Host C
Receiver
VLAN 30
VLAN 20
VLAN 10
Switch A
Host A
Receiver
Host B
Receiver
Host C
Receiver
VLAN 30
VLAN 20
VLAN 10
Figure 5-1
Before and after IPv6 multicast VLAN is enabled on the Layer 2 device
To solve this problem, you can enable the IPv6 multicast VLAN feature on Switch A,
namely configure the VLANs to which these hosts belong as sub-VLANs of an IPv6
multicast VLAN on the Layer 2 device and enable IPv6 Layer 2 multicast in the IPv6
multicast VLAN. After this configuration, Router A replicates the IPv6 multicast data
only within the IPv6 multicast VLAN instead of forwarding a separate copy of the IPv6
multicast data to each VLAN. This saves the network bandwidth and lessens the
burden of the Layer 3 device.
5.2 Configuring IPv6 Multicast VLAN
Follow these steps to configure IPv6 VLAN