Configuring IGMP on the interface that connects a multicast device to the user network segment implements the management of group members on the local network.
After the basic IGMP functions are configured on the interface that connects a multicast device to the user network segment, the hosts on the user network segment can access the multicast network and multicast packets can reach receivers.
The system supports IGMP Report message filtering through configurations of IGMP message options. For example, you can configure a device to deny or send IGMP messages with no Router-Alert options or filter IGMP Report messages based on source addresses.
An IGMP querier periodically sends IGMP Query messages on a shared network segment to refresh information about IGMP group members. IGMP parameters configured on all the interfaces of the multicast devices on the same network segment with the user host should be consistent; otherwise, a fault occurs on the network.
In the network segment where multicast services are provided in the Source-Specific Multicast (SSM) mode, the interface of the multicast device runs IGMPv3 while certain hosts can run only IGMPv1/v2 due to various limitations. To ensure that the multicast device running a later IGMP version is compatible with the hosts running an earlier IGMP version and provides the SSM service for these hosts, configure static SSM mapping on the multicast device.
To limit IPTV ICPs and the number of user accesses on IP core networks, you can configure the IGMP limit function. Configuring the IGMP limit function involves setting the maximum number of global IGMP group memberships, maximum number of global IGMP group memberships in a single instance, and maximum number of IGMP group memberships on an interface.