2-1
3 Multicast VLAN Configuration
When configuring multicast VLAN, go to these sections for information you are interested in:
z Introduction to Multicast VLAN
z Multicast VLAN Configuration Task List
z Configuring Multicast VLAN
z Displaying and Maintaining Multicast VLAN
z Multicast VLAN Configuration ExampleMulticast VLAN Configuration Examples
Introduction to Multicast VLAN
As shown in Figure 3-1, in the traditional multicast programs-on-demand mode, when hosts, Host A,
Host B and Host C, belonging to different VLANs require multicast programs on demand service, the
Layer 3 device, Router A, needs to forward a separate copy of the multicast traffic in each user VLAN to
the Layer 2 device, Switch A. This results in not only waste of network bandwidth but also extra burden
on the Layer 3 device.
Figure 3-1 Multicast transmission without multicast VLAN
The multicast VLAN feature configured on the Layer 2 device is the solution to this issue. With the
multicast VLAN feature, the Layer 3 device needs to replicate the multicast traffic only in the multicast
VLAN instead of making a separate copy of the multicast traffic in each user VLAN. This saves the
network bandwidth and lessens the burden of the Layer 3 device.
The multicast VLAN feature can be implemented in two approaches, as described below:
As shown in Figure 3-2
, Host A, Host B and Host C are in three different user VLANs. All the user ports
(ports with attached hosts) on Switch A are hybrid ports. On Switch A, configure VLAN 10 as a multicast
VLAN, assign all the user ports to this multicast VLAN, and enable IGMP Snooping in the multicast
VLAN and all the user VLANs.
To Next Page
Loading...
Need help?
General