Enhanced Interior Gateway Routing Protocol. EIGRP requires much less processing time, memory and design effort than OSPF. However, EIGRP is Cisco-proprietary, so if an internetwork uses some non-Cisco routers, EIGRP cannot be used on those routers.

EIGRP does not fit neatly into the general categories of distance vector and link-state routing protocols. Sometimes Cisco refers to EIGRP as an advanced distance vector protocol, or a new type: a balanced hybrid routing protocol.

It includes the following topics -