3Com 5500-SI Switch User Manual


 
IGMP Snooping 319
If IGMP fast leave processing is enabled, when receiving an IGMP Leave message,
IGMP Snooping immediately removes the port from the multicast group. When a port
has only one user, enabling IGMP fast leave processing on the port can save
bandwidth.
Configuring IGMP
Snooping Filter ACL
You can configure multicast filter ACLs globally or on switch ports to use the IGMP
Snooping filter function to limit the multicast programs that the users can order. With
this function, you can treat different VoD users in different ways by allowing different
users to order different groups of programs.
In practice, when a user orders a multicast program, an IGMP report message is
generated. When the message arrives at the switch, the switch examines the
multicast filter ACL referenced on the access port to determine if the port can join the
corresponding multicast group or not. If yes, it adds the port to the forward port list
of the multicast group. If not, it drops the IGMP report message and does not forward
the corresponding data stream to the port. In this way, you can control the multicast
programs that users can order.
Configuring the
Maximum Number of
Multicast Groups on a
Port
You can use the command here to limit the number of multicast groups on a switch
port. After that, users on this port cannot unlimitedly order multicast programs
because you have limited the number of multicast groups on this port. In this way,
you can control the multicast bandwidth on a port.
Table 314 Enable IGMP fast leave processing
Operation Command Description
Enter system view system-view
Enter Ethernet port view interface interface-type
interface-number
Enable IGMP fast leave
processing
igmp-snooping fast-leave
vlan vlan-id [ to vlan-id ]
Required
By default this function is
disabled.
Table 315 Configure IGMP Snooping filter ACL
Operation Command Description
Enter system view system-view
Enable IGMP Snooping
filter in system view
igmp-snooping group-policy
acl-number vlan vlan-list
Required
acl-number is the number of a
basic ACL; vlan-id is a VLAN ID. By
default, this function is not
enabled.
Enter Ethernet port view interface interface-type
interface-number
Configure an IGMP
Snooping filter ACL on
the port
igmp-snooping group-policy
acl-number vlan vlan-list
Required
acl-number is the number of a
basic ACL; vlan-id is a VLAN ID. By
default, no ACL is configured on
any port.
Table 316 Configure the maximum number of multicast groups on a port
Operation Command Description
Enter system view system-view
Enter Ethernet port view interface interface-type
interface-number