Users Guide

group-and-source query so that it can satisfy all other hosts. There are no other interested hosts so the
request is recorded.
Figure 51. Membership Reports: Joining and Filtering
Leaving and Staying in Groups
The following illustration shows how multicast routers track and refresh state changes in response to group-
and-specific and general queries.
1 Host 1 sends a message indicating it is leaving group 224.1.1.1 and that the included filter for 10.11.1.1 and
10.11.1.2 are no longer necessary.
2 The querier, before making any state changes, sends a group-and-source query to see if any other host
is interested in these two sources; queries for state-changes are retransmitted multiple times. If any are,
they respond with their current state information and the querier refreshes the relevant state information.
Internet Group Management Protocol (IGMP) 452