Research And Improvement Of The Aodv Routing Protocol

Mobile Ad Hoc Networks can rapidly build without the support of network infrastructure at any time, any place, because it with characteristics of multi-hop, no control center, the dynamic changes of network topology. Thought it has been widely used in military, civilian, and multimedia fields, the routing problem has been the research focus of the Ad Hoc Networks because of the limitations of the terminal equipment like energy, low performance and small memory.Ad Hoc On-Demand Distance Vector Routing (AODV) has provided high efficiency, good scalability routing solution for Mobile Ad Hoc Networks. However, AODV does not take the energy consumption and buffer consumption of the nodes in consideration, and the sole criterion for AODV is the shortest hops. The path established by AODV was not the best, and some nodes will exit the network because the energy depletion, and the energy consumption is not balanced in the network that established with AODV protocol, therefore the survival time of the network is reduced.First, this paper introduced the status of the Ad Hoc network, its application fields, its characteristics and a series of questions its facing currently. Based on the special circumstances of the Ad Hoc Networks, this paper studied the Protocol stack model of Ad Hoc Networks. Analysis the differences of the Pro-active Protocols, the Re-active Protocols and the load balancing Protocols, then illustrates the environments that each type of the protocols can maximize their efficiency. Based on the depth analysis of the inadequacies of the working mechanism of the AODV protocol in routing discovery phase and the routing maintenance phase, this paper put forward an E-AODV Protocol, which including delay in forwarding mechanism and node collapse mechanism. And in the last, E-AODV is implemented in Network Simulation Version2. Then assess the performance in some particular scenes from three aspects, and compare AODV and E-AODV in packets arrival rate, routing load, Network average delay. The results show that, the average delay in network of E-AODV is lower than AODV, and the routing load of E-AODV is smaller than AODV, and the packets arrival rate of E-AODV is higher than AODV when the nodes move fast in the network.