Enhanced Interior Gateway Routing Protocol (EIGRP) is a ______________ protocol created as a Cisco proprietary protocol that later became open standard.

• A. Balanced Hybrid
• B. Distance Vector
• C. Link State
• D. Path Vector

Answer: (A)

EIGRP is best described as a balanced hybrid routing protocol. It blends traits of distance-vector protocols—routing decisions based on a metric and neighbor updates—with some link-state-like features, such as maintaining topology information to enable fast, loop-free convergence using the DUAL algorithm. This approach lets it update efficiently and converge quickly without flooding full topology as a true link-state protocol would. The fact that EIGRP started as Cisco’s proprietary protocol and later became an open standard fits its hybrid nature, not strictly a pure distance-vector, link-state, or path-vector protocol. The other categories don’t fit because pure distance-vector lacks the topology-aware convergence behavior, link-state would imply full topology maps like OSPF, and path-vector is associated with protocols like BGP.