Allied Telesis AT-S63 - Manual (Page 300)

Chapter 18: IGMP Snooping
300 Section III: Snooping Protocols
switch learned the router on a port trunk, the trunk ID number, not the
port number, is displayed.
Router IP
The IP address of the multicast router.
ExpTime
The number of seconds remaining before the multicast router is timed
out if no further IGMP queries are received from it.