Abstract: Mobile Ad-hoc Network (MANET) is an infrastructure less and decentralized network which need a robust dynamic routing protocol. In such an environment, it may be necessary for one mobile host to enlist the aid of others in forwarding a packet to its destination, due to the limited propagation range of each mobile host’s wireless transmissions. Some previous attempts have been made to use conventional routing protocols for routing in ad hoc networks, treating each mobile host as a router. There have been several routing protocol proposed. In Manet protocols are classified in two categories Reactive and proactive protocol.The most efficient reactive protocol is Ad-hoc on demand distance vector (AODV) routing protocol. We examine AODV in term of advantage and limitation.