Route refresh
When the inbound policy-filter for a peer changes, the routes advertised by the peer must be presented to the policy-filter engine to take effect. This means that all the routes that were received from a peer will have to be preserved in the router and this would raise the demand on memory and CPU resources of the router. The route refresh capability allows the router to request the peer to re-advertise the routes thereby avoiding the requirement to keep a copy of all the routes that were received from all the peers.