5. Terminology and Concepts

We use the term "route reflection" to describe the operation of a BGP speaker advertising an IBGP learned route to another IBGP peer. Such a BGP speaker is said to be a "route reflector" (RR), and such a route is said to be a reflected route.

The internal peers of an RR are divided into two groups:

1. Client peers
2. Non-Client peers

An RR reflects routes between these groups, and may reflect routes among client peers. An RR along with its client peers form a cluster. The Non-Client peer must be fully meshed but the Client peers need not be fully meshed. Figure 3 depicts a simple example outlining the basic RR components using the terminology noted above.

              / - - - - - - - - - - - - -  -
              |           Cluster           |
                +-------+        +-------+
              | |       |        |       |  |
                | RTR-A |        | RTR-B |
              | |Client |        |Client |  |
                +-------+        +-------+
              |       \           /         |
                 IBGP  \         / IBGP
              |         \       /           |
                        +-------+
              |         |       |           |
                        | RTR-C |
              |         |  RR   |           |
                        +-------+
              |           /   \             |
               - - - - - /- - -\- - - - - - /
                  IBGP  /       \ IBGP
               +-------+         +-------+
               | RTR-D |  IBGP   | RTR-E |
               |  Non- |---------|  Non- |
               |Client |         |Client |
               +-------+         +-------+

                  Figure 3: RR Components