Research And Implementation Of SP_AODV Routing Protocol Based On Node Stability And Routing Failure Prediction

A mobile Ad Hoc network (MANET) can establish a mobile communication network rapidly at any time and any place without the support of fixed infrastructure. MANETs are flexible and have a wide applications prospect. MANETs have been mainly deployed in emergency rescue, disaster relief, military field, sensor networks and so on. However there are also many issues in MANETs, such as dynamic changes of network topology, limited energy and bandwidth, security, etc., which make it very difficult to design a perfect routing protocol. The routing protocols of MANETs have become one of the research hot spots in the network area at home and abroad.On the basis of investigating the classical routing protocols and considering the characteristics of MANETs, this thesis proposes a modified routing protocol based on node stability and routing failure prediction named SP_AODV. SP_AODV has three aspects of improvement. On the one hand, we propose a routing mechanism based on node stability which takes into account the remaining energy and communication status of current node and based on which SP_AODV presents a latency algorithm.The algorithm can guarant that the intermediate nodes chose to establish path have the sufficient power and are in a relative idle status during the route discovery phase. So the established path has higher stability and longer life. On the other hand, in order to forecast link failure caused by the deficient energy shortage in advance, this thesis presents an algorithm for routing failure prediction. It can reconstruct or repair the routes before the link failure due to some nodes lack of energy to promote the packet delivery ratio and reduce the end-to-end delay. Finally, for the purpose of reducing costs and shortening time of the local repair, SP_AODV improves the local repair process.This thesis gives a detailed description about SP_AODV routing protocol and implemention of the SP_AODV on NS2network simulation platform. Then we implement some simulation experiments of SP_AODV and AODV by varying the values of CBR sending rate, maximum number of connections among nodes and the maximum mobile speed of the node. Finally, this thesis analyzes the experimental result, and then compares the performance between SP_AODV and AODV on packet delivery ratio, end-to-end delay and routing overhead, meanwhile analyzes the reasons for the differences of performance. The evaluation indicates that the proposed protocol modifies the performance of network in these three aspects on different levels compared with AODV. Especially in the heavy load network, the performance of SP_AODV is better.