Research On Routing In DTNs And Applications In VANETs

With the development of Intelligent Transportation System recent years, VANETis playing an important role in may ways such as the applications of early warning,distributed traffic information publishing, computer-aided driving, information servicesand entertainment services. Especially in the remote areas where the communicationinfrastructure is weak, VANET has became an effective methods of traffic informationtransmission. However, the network is interrupted frequently in the city becase of thehigh vehicle speed, uneven distribution of vehicle, the traffic rules, obstacle factors,which makes it difficult to create the routing path from end to end. So, designing anefficient routing protocol in order to ensure the information transmission timely andreliable has been the hot and difficult field of VANET research.This paper summarizes the exiting routing protocols of Vehicular Ad-hoc Network(VANET), analyses the abuse of the current routing protocols. This paper also detailedanalyses the characteristics, network architecture and summarizes the exiting routingprotocols of Delay Tolerant Network (DTN). Detailed study of the Spray and Waitrouting algorithms and in view of the message copies would be distributed prematurelyin the high node density areas, the message copies are limited to a local area whichcause a long time delay and low delivery ratio and a node density adaptive routingalgorithm (NDASF) is proposed. According to the thought of NDASF routing algorithmin DTN, the Protocol Based on Attribute of Message algorithm (PBAM) is proposedwhich is applicable in the DTN scene to solve the problem in VANET. PBAM calculatesthe number of copies of the message according to the message properties and thenumber of nodes in the network. By estimating the node density of the current nodelocation, PBAM could control the available distributed number of message copies, andaccording to the driving direction of the neighbor vehicles control the fording directionof message so that the message is always forward towards the destination node.Through the LET, automatically adjust the size of the message to ensure the reliabilityof the transmission.This paper uses the simulation tool ONE as experimental platform, by simulatingdifferent scenarios, experiments were conducted to evaluate the indicators of theproposed routing protocols. By comparing with the other routing protocols show that the performance of the proposed routing algorithm has improved such as the successfulpacket deliveries rate, average delay, network overhead.