Advanced IP Network Design (CCIE Professional Development)

Case Study: Controlling Query Propagation

Not only do summarization statements and/or distribute lists limit the size and content of the updates sent to neighbors from a router, they also control the scope of EIGRP query propagation. (See Appendix C for further details on the query process.) Look at Figure 7-11 and consider a query propagating through this network.

Figure 7-11. Controlling Query Propagation

If Router B loses its route to 172.30.8.0/24, which is directly attached, it will query each of its neighbors in search of a different path to reach this destination. Because Router B has only one neighbor, the only router that will receive ...