Route policy overview

The route table in a routing switch contains routing paths to IP destinations. The traditional sources of the routing paths are:
  • Directly connected destinations (no router hops)

  • Static routes (manually configured by a network administrator)

  • Routing protocols such as RIP or OSPF

Route policy provides an additional method for controlling entries in the route table. This approach applies predetermined policies to define how the routing switch accepts routes from peers, propagates routes to peers, and redistributes routes between different protocols. Route policy can often provide finer control and greater flexibility over route table entries than traditional methods.

Route policy is embodied in route maps, which are used to match destination routes according to IP addresses and other parameters. Optional set statements allow changing properties of the route depending on the match. Typical uses for route policy include filtering and redistribution of routes.

Route policy components