Cisco Systems 4500 Configuring IGMP Filtering

23-20
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 23 Configuring IGMP Snooping and Filtering
Configuring IGMP Filtering
Vlan 2: IGMP switch querier status
------------------------------------------------
admin state : Enabled
admin version : 2
source IP address : 1.2.3.4
query-interval (sec) : 55
max-response-time (sec) : 12
querier-timeout (sec) : 70
tcn query count : 10
tcn query interval (sec) : 8
operational state : Querier
operational version : 2
tcn query pending count : 0
Configuring IGMP Filtering
This section includes the following subsections:
• Default IGMP Filtering Configuration, page 23-20
• Configuring IGMP Profiles, page 23-21
• Applying IGMP Profiles, page 23-22
• Setting the Maximum Number of IGMP Groups, page 23-23
Note The IGMP filtering feature works for IGMPv1 and IGMPv2 only.
In some environments, for example metropolitan or multiple-dwelling unit (MDU) installations, an
administrator might want to control the multicast groups to which a user on a switch port can belong.
This allows the administrator to control the distribution of multicast services, such as IP/TV, based on
some type of subscription or service plan.
With the IGMP filtering feature, an administrator can use this type of control. With this feature, you can
filter multicast joins on a per-port basis by configuring IP multicast profiles and associating them with
individual switch ports. An IGMP profile can contain one or more multicast groups and specifies
whether access to the group is permitted or denied. If an IGMP profile denying access to a multicast
group is applied to a switch port, the IGMP join report requesting the stream of IP multicast traffic is
dropped, and the port is not allowed to receive IP multicast traffic from that group. If the filtering action
permits access to the multicast group, the IGMP report from the port is forwarded for normal processing.
IGMP filtering controls only IGMP membership join reports and has no relationship to the function that
directs the forwarding of IP multicast traffic.
You can also set the maximum number of IGMP groups that a Layer 2 interface can join with the
ip igmp max-groups n command.
Default IGMP Filtering Configuration
Table 23-2 shows the default IGMP filtering configuration.