Route Reflectors

One way to overcome the difficulties of creating a fully meshed AS is to use route reflectors. Route reflectors allow a single router to serve as a central routing point for the AS. All BGP speakers in the AS will peer with the route reflector to learn routes.

A cluster is formed by the route reflector and its client routers. Peer routers that are not part of the cluster must be fully meshed according to the rules of BGP.

A BGP cluster, including the route reflector and its clients, is shown in Route Reflectors.

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Route Reflectors

This topology minimizes the number of BGP peering sessions required in an AS by using a route reflector.

In this example, although the BGP speakers and do not have a direct BGP peering session between them, these speakers still receive routes from each other indirectly through The router is called a route reflector and is responsible for reflecting routes between its clients. Routes received from the client by the router are reflected to and vice-versa. Routes received from are reflected to all clients.