Route Types

The routing table can contain six types of routes:

Host route

A host route is a route to a host. In other words, the route is not to a network. Host routes have a subnet mask of 255.255.255.255, and a prefix length of /32.

Subnet

A subnet is a portion of a major network. The subnet mask is used to determine the size of the subnet. 10.10.10.0/24 (255.255.255.0) is a subnet.

Summary (group of subnets)

A summary route is a single route that references a group of subnets. 10.10.0.0/16 (255.255.0.0) would be a summary, provided that subnets with longer masks (such as 10.10.10.0/24) existed.

Major network

A major network is any classful network, along with its native mask. 10.0.0.0/8 (255.0.0.0) is a major network.

Supernet (group of major networks)

A supernet is single route that references a group of major networks. 10.0.0.0/7 is a supernet that references 10.0.0.0/8 and 11.0.0.0/8.

Default route

A default route is shown as 0.0.0.0/0 (0.0.0.0). This route is also called the route of last resort. This is the route that is used when no other route matches the destination IP address in a packet.

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