Enhanced Interior Gateway Protocol (EIGRP) is a Cisco proprietary distance vector routing protocol. It is based on the Diffusing Update Algorithm (DUAL), which is a method of finding loop-free paths through a network. Directly connected routers running EIGRP form neighbor adjacencies in order to propagate best-path and alternate-path routing information for configured and learned routes. The tables defined within the MIB are closely aligned with how the router command-line interface for EIGRP displays information on EIGRP configurations, i.e., the topology table contains objects associated with the EIGRP topology commands, and the peer table contains objects associated withe EIGRP neighbor commands, etc. There are five main tables within this mib: EIGRP VPN table Contains information regarding which virtual private networks (VPN) are configured with EIGRP. EIGRP traffic statistics table Contains counter & statistcs regarding specific types of EIGRP packets sent and related collective information per VPN and per autonomous system (AS). EIGRP topology table Contains information regarding EIGRP routes received in updates and originated locally. EIGRP sends and receives routing updates from adjacent routers running EIGRP with which it formed a peer relationship. EIGRP peer (neighbor) table Contains information about neighbor EIGRP routers with which peer adjacencies have been established. EIGRP uses a Hello protocol to form neighbor relationships with directly connected routers also running EIGRP. EIGRP interfaces table Contains information and statistics on each of the configured to run. RIB-scale ========== The Wide-Metrics feature calculates all metrics in 64-bit under named mode EIGRP. Since the RIB can only hold 32-bit, we divide the wide metrics by RIB-scale (range 1-255, default value 128) to convert it to a 32-bit value before assiging it to RIB metrics.