3Com Switch 8800 Family Configuration Guide

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MULTICAST VLAN CONFIGURATION
Multicast VLAN
Overview
Based on the current multicast on demand, when users in different VLANs request
the service, multicast flow is duplicated in each VLAN and thus a great deal of
bandwidth is wasted. To solve this problem, we provide the multicast VLAN
feature. With this feature, you can add switch ports to a multicast VLAN and
enable IGMP Snooping to allow users in different VLANs to share the same
multicast VLAN. In this way, multicast flow is transmitted in one multicast VLAN
instead of multiple user VLANs and bandwidth is greatly saved.
As multicast VLAN is isolated from user VLANs, this guarantees both security and
enough bandwidth. After you configure the multicast VLAN, multicast information
flow can be transmitted to users continuously.
Multicast VLAN
Configuration
Multicast VLAN is based on layer 2 multicast. The following table describes the
multicast VLAN configuration tasks:
n
■ A port can only belong to one multicast VLAN.
■ The type of the ports connected to user terminals must be hybrid untagged.
■ The current system supports up to three multicast VLANS.
Tab le 421 Configure multicast VLAN
Item Command Remarks
Enter system view system-view -
Enable IGMP Snooping in
system view
igmp-snooping enable Required
Enter VLAN view vlan vlan-id -
IGMP Snooping is enabled on
the VLAN
Enable IGMP Snooping in
VLAN view
igmp-snooping enable Required
Enable multicast VLAN service-type multicast Required
Quit VLAN view quit
Enter the view of the Ethernet
port connected to the user
interface interface-type
interface-number
-
Define the port type to hybrid port link-type hybrid Required
Add ports to corresponding
VLANs
port hybrid vlan vlan-id-list
untagged
Required