Static Routing

Static routing is the simplest routing known, where the router uses manually entered commands to decide which route packets are to take. The administrative distance of a static route is 1, with a metric of 0.

All routes include a next hop gateway and the destination network to be reached through that gateway. Static entries have to be manually entered into each router, making this a routing configuration not very accepting of change, and not able to be widespread in a large network. However, they are useful for default gateways and for forced configurations.

A router will always pick the most descriptive route it can - if it had a packet destined for the host 10.1.200.1, and it had two routes to the destination - one for 10.1.0.0 and one for 10.1.200.0, it would pick the latter, even if the administrative distance of the latter was higher.

In order of decreasing specificity, the address will go along one of the following:

1. A host address
2. A subnet
3. A group of subnets (summary route)
4. A major network number
5. A group of major network numbers (supernet)
6. A default address

Important: If given a choice between two static routes for identical destinations, and one references a next-hop address while one references an exit interface, the latter will be preferred.

Static routes support only equal-cost load sharing. Per-destination load balancing is performed using fast switching by default, and per-packet load balancing is performed using process switching.