Research On Dynamic Handoff Algorithms In Dtn Routing For Mobile Relay

DTN,as a new type of communication network,is proposed to solve the challenging network problems that can not be solved by the traditional Internet.In the current research of DTN network,the research of routing algorithm is the most important.In challenge networks,communication opportunities between nodes are created by the mobility of nodes.Most of the nodes in the urban environment have mobility and fixed movement characteristics.Therefore,it is feasible to use DTN network to send message packets with low timeliness and large amount of data in the urban environment.Mobile relay nodes using only a single routing algorithm in the whole network operation process can only show better routing performance at special times,because they can not reasonably utilize the caching resources of the nodes,which will have certain limitations.Therefore,this paper designs and implements a DTN routing dynamic handoff algorithm for mobile relay nodes in the simulator.Firstly,on the basis of a thorough understanding of the DTN network protocol system and the unique mode of message transmission,this paper first makes a theoretical analysis of the classical routing algorithms of DTN,and summarizes the applicable scenarios of the classical routing algorithms.Then it introduces the simulator ONE which is often used in the research of DTN routing algorithm,and according to the need of this research,the routing module and reporting module in ONE are analyzed and introduced in detail.Secondly,based on the analysis of the principle of DTN classical routing algorithm in the second chapter,according to the problems of node cache resource constraints faced by deploying routing algorithm in mobile relay nodes,the performance of four classical routing algorithms is evaluated and analyzed with the help of ONE simulation platform under the condition of cache resource constraints.The factors that limit the performance of DTN routing algorithm in mobile relay nodes are pointed out.According to these constraints,a dynamic routing handoff algorithm combining local cache resources is proposed.This algorithm analyses the factors that affect the caching resources of nodes from two aspects.Firstly,according to the different message queues of different nodes and the different message attribute values in the queue,a node message value model is proposed.Secondly,according to the interaction relationship between neighbor nodes through message interaction in the network,a model of mutual influence factors between nodes is proposed,and the load rate and message value of current nodes are modified by this model.On this basis,a dynamic routing handoff algorithm combining local cache resources is proposed.Finally,the DTN routing dynamic handover algorithm is implemented in the simulator ONE.Under the same simulation environment parameters,the performance of dynamic routing handoff algorithm is verified by experiments.Compared with the classical routing algorithm,the effectiveness of the algorithm is validated.