Research And Improvement On Routing Protocol Of Mobile Ad Hoc Networks

With wireless communication and mobile terminal making great progress, wireless Ad hoc network is widely applied not only in military realm but also civil realm.Wirelss Ad hoc network have many characteristics: any node in the network can randome move; network topological structure dynamic change etc.Because of them, there are many problems and challenges in routing researching of wireless Ad hoc network.This paper detailes study of the Ad Hoc network routing protocols, focusing on analysis of two typical on-demand routing protocols (DSR and AODV). In the diffient case of the network load, it compares the performance DSR and AODV protocol in NS2. Simulation results show that: AODV performance is limited, especially the number of Route Request packets in the route discovery process restrict AODV routing protocol development. Meanwhile, the paper focuses the cross-layer design method which is one of hot methods to improve AODV's performance. Combinating with my own understanding, it organizes and analyzes the relevant theoretical knowledge to provide a theoretical basis in order toimprove the performance of AODV protocol.Based on the above study, the paper gives a new protocol-CLMAODV(Cross Layer Multi-path AODV). There are two aspects to improve AODV protocol in the new protocol: one is drawing on multi-path DSR protocol ideas, combined with cross-layer design approach, considering the node's life time and hop count to design a new multi-path selection principle in order to increase choice of optimal path opportunities; the other one is given an adaptive load-sensing mechanism to reduce the number of control packets, and enhance the stability of the path, considering the node load problem. In the NS2 simulation platform, the new protocol will compare with the former AODV protocol. The result shows that the routing load, delivery rate in the routing and throughput of the performance has improved significantly in CLMAODV protocol based on the performance of the original AODV protocol.