Configuring Multicast Vlan - 3Com 4500 Configuration Manual

Configuring Multicast VLAN

In traditional multicast implementations, when users in different VLANs listen to the same multicast
group, the multicast data is copied on the multicast router for each VLAN that contains receivers. This is
a big waste of network bandwidth.
In an IGMP Snooping environment, by configuring a multicast VLAN and adding ports to the multicast
VLAN, you can allow users in different VLANs to share the same multicast VLAN. This saves bandwidth
because multicast streams are transmitted only within the multicast VLAN. In addition, because the
multicast VLAN is isolated from user VLANs, this method also enhances the information security.
Multicast VLAN is mainly used in Layer 2 switching, but you must make the corresponding
configurations on the Layer 3 switch.
Follow these steps to configure multicast VLAN on the Layer 3 switch:
To do...
Enter system view
Create a multicast VLAN and
enter VLAN view
Return to system view
Enter VLAN interface view
Enable IGMP
Return to system view
Enter Ethernet port view for the
Layer 2 switch to be configured
Define the port as a trunk or
hybrid port
Specify the VLANs to be
allowed to pass the Ethernet
port
Follow these steps to configure multicast VLAN on the Layer 2 switch:
To do...
Enter system view
Enable IGMP Snooping
Enter VLAN view
Enable IGMP Snooping
Enable multicast VLAN
Return to system view
Use the command...
system-view
vlan vlan-id
quit
interface Vlan-interface
vlan-id
igmp enable
quit
interface interface-type
interface-number
port link-type { trunk |
hybrid }
port hybrid vlan vlan-id-list
{ tagged | untagged }
port trunk permit vlan vlan-list
Use the command...
system-view
igmp-snooping enable
vlan vlan-id
igmp-snooping enable
service-type multicast
quit
1-15
Remarks
—
—
—
—
Required
By default, the IGMP feature is
disabled.
—
—
Required
Required
The multicast VLAN defined on
the Layer 2 switch must be
included, and the port must be
configured to forward tagged
packets for the multicast VLAN
if the port type is hybrid.
Remarks
—
—
—
Required
Required
—