EIGRP is a shorthand for Enhanced Interior Gateway Routing Protocol. EIGRP is a Cisco-proprietary distance vector routing protocol designed to minimize time of convergence in a network. EIGRP provides guaranteed loop-free routes. It has the characteristics of both distance vector and link-state routing protocols. When something in the topology changes, only that change is advertised. However, EIGRP is still a distance-vector protocol, because it sends distance-vector updates. These updates contain the cost of reaching the network.