Research On DTN Epidemic Routing Methods With Congestion Control

Delay tolerant network is emerging as a new type of network architecture using point-to-point store and forward routing,gained the attention and research of many scholars and researchers in recent years.It is obviously different from the traditional network,with high delay,intermittent connection,resource constraints and other characteristics,so its routing protocol must to use ‘store-carry-forward' data forwarding mode.Generally,DTN network adopts multi-copy transmission routing strategy.This routing method increases the success rate of message transmission by increasing the number of message copies,and reduces the message forwarding delay.However,a large number of redundant copies will lead to congestion at nodes,resulting in reduced resource utilization of the network and even network congestion resulting in overall poor performance.Therefore,it is very necessary to study how to reduce the resource consumption of nodes and prolong the overall network lifetime.This article focuses on multi-copy routing strategy with efficient congestion control methods,the main contents are:Firstly,aiming at the problem of network congestion caused by limited node storage space,a congestion control method based on node storage state is proposed in this paper.The main idea is to divide the storage state into three states: normal,semi-congested and congested according to the storage utilization of the node.The node adjusts its own congestion control mechanism according to its own congestion condition,thus effectively balancing the load of nodes,avoiding the next hop node as the congestion node,and also realizing the rational utilization of network resources,reducing the probability of network congestion.Secondly,considering the stochastic dynamic changes of DTN network topology,this paper improves the infection routing algorithm based on the NSS-CC method and finally propose a DTN multi-copy routing method with congestion control ER2 C.In ER2 C Routing,a dynamic storage state model is introduced in this paper,that is,a node can sense the network condition and thus dynamically adjust the threshold of the node's semi-congestion state.In addition,in order to solve the problem of how to receive new information when there is not enough storage space in the node,this paper proposes a multi-attribute packet loss strategy.ER2 C routing can adapt to different levels of congestion network environment,more universal.Finally,using The simulation tool ONE to compare the network performance of NSS-CC and DO,DF,DY and DL in the infection routing algorithm,and in three different degree of congestion in network environment simulation experiment of ER2 C routing algorithm,combine it with the Epidemic and PROPHET routing algorithm in the message delivery ratio,average delay and average forwarding number,network load four aspects were compared.Simulation results show that the ER2 C method can better adapt to changes in the network environment,and has stable routing performance.