A BGP peer group is a group of BGP neighbors that share a common set of update policies. Update policies are usually defined by route maps, distribution lists, prefix lists, and filter lists. Instead of defining the same policies for each individual neighbor, you define a peer group name and assign policies to the peer group.
The network shown in Figure 11-3 demonstrates the use of BGP peer groups.
Figure 11-3. BGP Peer Groups
RTC forms similar internal peering sessions with RTD, RTE, and RTH. Instead of formulating and applying similar policies for each neighbor individually, RTC defines a peer group that contains the policies ...