Another 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.

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

Figure 80

Figure 80. Route Reflectors

EX_042

Client

Route Reflector

Non-client

10.0.0.1

10.0.0.2

30.0.0.1

30.0.0.2

20.0.0.2

20.0.0.1

1.1.1.1

2.2.2.2

3.3.3.3

Cluster

AS 100

Client

4.4.4.4