The Research On Epidemic Routing In Delay Tolerant Network

Delay Tolerant Network(DTN)is an intermittent wireless network.In such networks,the nodes are sparsely distributed,the state is unstable,and the network topology changes frequently.So it results in the data packet transmission delay and the loss rate of packet is not ideal.It may even be a long time in a disconnected state that can not guarantee an end-to-end transmission.Thus,DTN routing research is a big challenge,the relevant routing algorithm in DTN is also a hot research area.After researching the existing routing protocols,the paper proposed two new routing protocols on that basis of Epidemic Routing.The first one is group based Epidemic Routing:nodes are divided into different groups,and the “Epidemic” only happens within certain groups.When two nodes meet,they not only exchange their respective summary vector,but also interchange their own group information.It is able to deliver more messages,and the amount of replications drops in a big degree.Another one is direction angle based Epidemic routing,which is to choose appropriate a relay by calculating the direction angle according to the position information of the neighbors and the destination.By comparing the direction angles with the predetermined value,it can choose the next-hop node of transmission.The simulation indicates that this improved routing algorithm has better performances on the delivery probability and the average delay comparing with the traditional Epidemic routing.