On the surface a packet is a chunk of information but at the deeper level a packet is one unit of binary data capable of being transferred through a network. Delivering data packets for highly dynamic mobile ad hoc networks in a reliable and timely manner. Driven by this issue, an efficient Position-based Opportunistic Routing (POR) protocol which takes advantage of the stateless property of geographic routing. In proactive routing protocols the route discovery and recovery procedures are time and energy consuming process. Once the path breaks, data packets will get lost or be delayed for a long time until the reconstruction of the route, causing transmission interruption. but Geographic routing (GR) uses location information to forward data packets, in a hop-by-hop routing fashion. Greedy forwarding is used to select next hop forwarder with the largest positive progress toward the destination while void handling mechanism is triggered to route around communication voids. No end-to-end route need to be maintained, leading to GR’s high efficiency and scalability. In the operation of greedy forwarding, the neighbour which is relatively far away from the sender is chosen as the next hop. If the node moves out of the sender’s coverage area, the transmission will fail. In GPSR (a very famous geographic routing protocol), the MAC-layer failure feedback is used to offer the packet another chance to reroute.