The number of seconds that a router's Hello packets have not been seen before its neighbors declare the router down. This should be some multiple of the Hello interval. This value must be the same for all routers attached to a common network. Note that 1..65535 is for 'set' range ; The read value may be (1...65535)*4 by default according to the Hello interval if this dead interval has not been set. This is a private substitution for ospfIfRtrDeadInterval of RFC1253.