Fortinet Exam FCSS_EFW_AD-7.4 Topic 5 Question 4 Discussion

In an IBGP (Internal BGP) network, all routers must be fully meshed, meaning every router must establish a BGP session with every other router in the same autonomous system (AS). This does not scale well in large networks due to the exponential increase in BGP sessions.

To optimize and scale IBGP, Route Reflectors (RRs) are used. A Route Reflector (RR) reduces the number of IBGP peer connections by allowing a centralized router (RR) to redistribute IBGP routes to other IBGP peers (called clients). This eliminates the need for a full mesh, significantly reducing BGP session overhead.

By configuring the route-reflector-client setting on IBGP peers, an administrator can:

Scale IBGP sessions by reducing the number of direct BGP peer connections.

Optimize the routing table by ensuring routes are efficiently propagated within the IBGP network.

Eliminate the need for full mesh topology, making IBGP more manageable.