IGMP last member query interval
In IGMP, when a querier receives a Leave Group message, it sends a Group-Specific Query to the group being left. The Max Response Time, which by default is 10 seconds, in this query is set to the Last Member Query Interval, which by default is 1 second.
Links
https://datatracker.ietf.org/doc/html/rfc2236#page-5 https://datatracker.ietf.org/doc/html/rfc2236#section-8.8