Cisco ASR 9000 Series Routing Configuration Manual page 78

Implementing BGP
BGP Route Reflectors
route to other iBGP speakers because the routers do not pass on routes learned from internal neighbors to
other internal neighbors, thus preventing a routing information loop.
Figure 6: Three Fully Meshed iBGP Speakers
With route reflectors, all iBGP speakers need not be fully meshed because there is a method to pass learned
routes to neighbors. In this model, an iBGP peer is configured to be a route reflector responsible for passing
iBGP learned routes to a set of iBGP neighbors. In Figure 7: Simple BGP Model with a Route Reflector, on
page 49 , Router B is configured as a route reflector. When the route reflector receives routes advertised from
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
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