Research Of Improved DTN Routing Protocol On Highway Environment

Nowadays, the mainly research on the protocol of mobile vehicle network is based on the connected networks. But this method has its limitations. The majority nodes in this network have the constraint that they are required to connect with at least one other node most of the time. The message will not transmit successfully if there is no path from source node to the destination. So it always can not acquire the anticipative effects when applies the traditional routing protocols in the radio link instability networks.The research of highway movement model that studied in the paper has just proposed under this background. Because the nodes in this circumstance have very high speed, and the network topology structure changes very quickly. This makes the node's radio link instability and it is very difficult to ensure there is a stable transmission link between the two nodes. This environment makes the traditional method not perform well.According to the feature of vehicle movement, this article proposed the particular request that applied DTN architecture to the highway environment. Ordinary DTN protocol only uses single node as the unit of message storing and forwarding. But possibility of the appearance of single node is greatly reduced on the highway. It will result in the resource waste if we perform it as past. This article proposes a hybrid DTN-DSR protocol to handle this problem. This protocol adopts an effective leader election algorithm to improved existing cluster-based method and uses a hybrid protocol after the grouping. It is very suitable to adopt this hybrid protocol which uses DTN between disjoint groups of nodes while using DSR routing within these groups.At last, this article uses Qualnet simulation software to evaluate the performance of the routing protocol proposed. We performed an experiment to compare the DSR, EPI with the improved protocol. We found that the improved protocol have a better performance on message delivery ratio and average delay than DSR and EPI.