MANET is a decentralized autonomous system in which different nodes are connected to each by wireless links. Nodes in the network can be either fix or mobile. Mobile nodes may include laptop, mobile phones, MP3 Player. Nodes may be located on ships, airplanes, land irrespective of their location as they can participate in communication. To facilitate the communication within the network, a routing protocol is used to discover the routes between nodes. The primary goal of such an network routing protocol is correct and efficient route establishment between a pair of nodes so that message can be deliver in a timely manner. Route construction should be done with a minimum of overhead and bandwidth consumption. This paper provides an overview of different Geographical routing protocols with their merits and drawbacks.
