what is administrative distance in router

ad value is an arbitrary numerical value assign to routing protocol it define the trustworthiness of a protocol for selecting routes to be place on routing table
if a router has routes to same destination from two protocols it will prefer the lowest ad value
if our ad value is lower the another value so router chose lower  ad (administrative distance) value for path


Here Some Default value of cisco supports router
Routing protocol                                          Default  value
Directly connected interface                         0
static routes                                                   1





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