Route routing principle

1. Management distance (administrative Distance)

The administrative distance is a reference value that provides the routing confidence, the smaller the administrative distance, the more reliable the routing entry. The management distance range 0-255,0 is the most reliable, and 255 means there is no traffic going through this route.

The default administrative distances for each routing protocol are as follows:

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2. Route routing principle

A, subnet mask longest match

If a destination address is overwritten by more than one network target, it chooses the longest subnet mask for the route.

b, the minimum management distance priority

In the case where the subnet mask length is the same, the router prioritizes the routing entry that manages the minimum distance.

C, the measure value is least first

If the subnet mask length of the route is equal, the administrative distance is equal, and the comparison measure is followed, the smallest measure enters the routing table.

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Route routing principle