CCNP Routing and Switching ROUTE 300-101 Official Cert Guide

Building the EIGRP Topology Table

The overall process of building the EIGRP topology table is relatively straightforward. EIGRP defines some basic topology information about each route for each unique prefix/length (subnet). This basic information includes the prefix, prefix length, metric information, and a few other details. EIGRP neighbors exchange topology information, with each router storing the learned topology information in its respective EIGRP topology table. EIGRP on a given router can then analyze the topology table, or topology database, and choose the best route for each unique prefix/length.

EIGRP uses much simpler topology data than does OSPF, which is a link-state protocol that must describe the entire topology of a portion ...