Research On Analysis Of Dynamic Topology And Approach Of Adaptive Routing For MANET

Mobile Ad Hoc Networks(MANET)is a non-central wireless multi-hop data transmission network composed of any mobile wireless terminal self-organizing.It has the characteristics of flexible networking and low cost in an environment lacking basic fixed facilities,a communication network is established,which broadens the application environment of the mobile data transmission network.In emergency or temporary situations such as emergency disaster relief without fixed transmission equipment,MANET plays an important role because it is the only optional data transmission method.While MANET gains excellent features,it also increases the complexity of its network-related design.Due to its strong mobility,no fixed topology,and limited resources,MANET still has many problems to be studied and solved.For example,the dynamic change of network topology structure,the adaptability and efficiency of routing,and self-repairing of routing etc.Aiming at these problems,this dissertation combines complex theory to analyze the dynamic change of topology structure when the random failures occur in MANET.It also analyses the efficiency of network for the DSR,which is the key route of on-demand routing.And the problem of self-repair for TORA is studied.That is to say,the topic of this dissertation is the ?Research on Analysis of Dynamic Topology and Approach of Adaptive Routing for MANET?.The specific research contents and innovations of this dissertation are as follows:For the nodes that enter the real network generally having the characteristics of location choice,the Evolving Network Model based on Local-Area Choice(ENM-LAC)is proposed for MANET networks according to the Complex network theory.The proposed topology model not only considers the actual mobility of nods for MANET and the scale-free nature of the network,but also considers the consumption of the node energy.In order to describe the impact of random edge failures on the topology of MANET,this dissertation focuses on the average shortest path length(ASPL)which is an important feature of the network topology,and proposes the formula for calculating the ASPL of the MANET after the random edge failure.The experimental simulation analyzes the change of the ASPL of MANET in the random failure scenario(after random edge deletion).By comparing with the actual scene results,the proposed estimation formula which describes this change more accurately is proved.The formula proposed in this dissertation provides a general framework for studying the shortest path of MANET.For dynamic source routing protocol(DSR),the choice of routing path only adopts the simplest minimum hop count algorithm when searching the routes to the destination nodes.In order to improve the control overhead of the network,this dissertation comprehensively consider the node energy informationan and propose a genetic algorithm(GA)-bacterial foraging optimization algorithm to perform the selection of theoptimal routing.After searching out multiple routes to the destination node,the GA algorithm is started.A number of optimized paths is quickly searched out,that is,the position where the maximum probability of the optimal path is located,and is taken as the initial position distribution of bacterial flora in the bacterial foraging algorithm.Using the characteristic of finding easily the extreme value for BFO algorithm,the optimal path is searched out.The proposed optimization strategy improves the routing algorithm without changing the complexity of DSR,and proves that the algorithm converges to the global optimal solution.The simulation results show that the new algorithm is feasible and applicable,and has good experimental results.In order to improve the short comings of temporally Ordered Routing Algorithms(TORA)in routing maintenance,such as high overhead and delay,and make the routing more suitable for emergency and disaster relief network,this dissertation proposes an adaptive repair algorithm for TORA routing protocol based on flood control strategy(AR-TORA-FCS).The self-repair process of the self-repair nodes in Directed acyclic graph(DAG)of TORA is transformed into the optimal search problem for the optimal nodes,and the formula is established.Then,a conditional algorithm to determine the self-repair process is given,and the path repair is carried out before the path fails.In order to reduce control overhead,an algorithm to determine the optimization region is proposed.Simulation results show that the algorithm reduces control overhead,improves the packet delivery rate,and improves average end-to-end delay.The mobile device,which is subject to unified deployment,is used as a network node to test the proposed adaptive repair algorithm in the actual rescue and disaster relief environment.The results show that it is basically consistent with the simulation results,and the overall performance is improved significantly.