Configuring Explicit Host Tracking - Juniper JUNOSE 11.0.X MULTICAST ROUTING Configuration Manual

JUNOSe 11.0.x Multicast Routing Configuration Guide
ip igmp static-include

Configuring Explicit Host Tracking

Explicit host tracking enables the router to explicitly track each individual host that
is joined to a group or channel on a particular multi-access network.
Explicit host tracking provides the following:
When the router is configured for explicit host tracking and starts immediate leave
using the host information collected, every leave message received for a group or
channel is treated as follows:
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Configuring Explicit Host Tracking

Use the no version to remove the static designation.
See ip igmp static-exclude.
Use to statically include the IGMP (S,G) membership for a host that is not capable
of dynamically signaling group membership.
Example
host1:boston(config-if)#ip igmp static-include 10.1.1.1 225.1.2.3
Use the no version to remove the static designation.
See ip igmp static-include.
Minimal leave latency when a host leaves a multicast group or channel. When
the router receives a leave message for a group or channel on an interface, it
accesses a list of hosts and immediately stops forwarding traffic if the sender is
the last host to request traffic for that group or channel. The leave latency is
bound only by the packet transmission latencies in the multi-access network
and the processing time in the router.
Ability to change channels quickly in networks where bandwidth is constrained
between a multicast-enabled router and hosts.
Ability to determine what multicast hosts are joined to particular multicast groups
or channels, which is useful for accounting purposes.
Reduction of control message traffic on the network because, when it receives
a leave message, the router no longer needs to send out IGMP queries to verify
membership. As a result, interested hosts also do not need to respond to these
queries with reports.
Tracking based on the IGMP reports for hosts in both include and exclude modes
for every multicast group or channel on an interface.
The router checks the number of hosts that receive traffic from the group or
channel.
If the host sending the leave message is the only host, it starts immediate leave
for that group or channel on that interface. The router removes the interface
from the multicast group or channel immediately, without sending out a group
or group-source-specific query and waiting for the last member query interval.