This read-create Unsigned32, in seconds, sets how long a DVMRP neighbor should continue considering this router operationally up after its last Hello message. An admin raises or lowers it relative to the Hello interval to control how tolerant neighbors are of missed Hellos before declaring this router down, trading faster failure detection against false positives from transient packet loss. For example, the default of 35 seconds against a 10-second Hello interval allows a neighbor to miss a few Hellos before assuming the router is down.