Multicast subsecond convergence provides the ability to trigger a check of RPF changes for mroute states. This check is triggered
by unicast routing changes. By performing a triggered RPF check, users can set the periodic RPF check to a relatively high
value (for example, 10 seconds) and still fail over quickly.
The triggered RPF check enhancement reduces the time needed for service to be restored after disruption, such as for single
service events (for example, in a situation with one source and one receiver) or as the service scales along any parameter
(for example, many sources, many receivers, and many interfaces). This enhancement decreases in time-to-converge PIM (mroute),
IGMP, and MSDP (SA cache) states.