Route policies are created in the config>router context. There are no default route policies. Each route policy must be explicitly created and applied. Applying route policies can introduce more efficiency as well as more complexity to routers.
A route policy impacts the flow of routing information or packets within and through the router. A routing policy can be specified to prevent a particular customer’s routes to be placed in the route table which causes those routes to not forward traffic to various destinations and the routes are not advertised by the routing protocol to neighbors.
Route policies can be created to control:
a protocol to export all the active routes learned by that protocol
route characteristics to control which route is selected to act as the active route to reach a destination and advertise the route to neighbors
protocol to import all routes into the routing table. A routing table must learn about particular routes to be able to forward packets and redistribute to other routing protocols
damping
Before a route policy is applied, analyze the policy’s purpose and be aware of the results (and consequences) when packets match the specified criteria and the associated actions and default actions, if specified, are executed. Membership reports can be filtered based on a specific source address.