Design And Implementation Of Data Forwarding Model For Vehicular Named Data Networks

With the rapid development of the Internet of Things,people's requirements for automobiles have also been continuously improved,and the construction of intelligent transportation has become a hot topic.Because the current network architecture used is the IP system,there is a certain gap between the car networking that currently appears on the market and the true sense of car networking.In order to narrow this gap,a content-centric data naming network architecture(NDN network)was proposed.The NDN network architecture is more applicable to the specific scenarios of Vehicular networking than the IP address-centered architecture of the host network.The NDN network architecture is more applicable to the specific scenarios of Vehicular networking than the IP address-centered architecture of the host network.In essence,the difference between the NDN network architecture and the IP network architecture is that the content naming data is used to replace the IP address.The focus of attention has shifted from the data acquisition method to the data itself.At the same time,each node in the NDN network architecture also has a caching mechanism,so that the efficiency of data acquisition can be improved through the widespread distribution of data.At present,there are still some challenges in the process of combining the NDN network architecture with the vehicle networking,especially among high-speed moving vehicle nodes,and interest packet forwarding has always been one of the research hotspots.Therefore,in view of the large amount of lost information and heavy retransmission overhead caused by the flooding broadcasting strategy,this paper proposes a data forwarding model for car naming network that is suitable for urban road environment.Since the data is transmitted along the trajectory forwardedby the interest packet,the design of the forwarding model in this paper is mainly directed to the forwarding trajectory of the interest packet.First of all,the forwarding model limits the vehicle nodes that receive the Interest packages in order to avoid excessive overhead of buffering Interest packages.Secondly,using the position coordinates of the target node as the starting point,it is judged whether the node itself is suitable for forwarding the interest packet through the inter-node algorithm and the intersection node algorithm in the geographical location route.The forwarding path formed by these reasonable forwarding nodes guarantees the reliability and efficiency of the interest packet delivery.In a geo-location routing forwarding algorithm,an inter-node Road Node Judgement Algorithm(RNJA)is used when both a node and a previous-hop node are located between roads.The position prediction is performed through the change of the relative position between the previous hop node and the transmission pressure of the node to determine whether the current node is suitable for forwarding the interest packet.This algorithm not only reduces the average delay but also equalizes the transmission capacity of the entire network.When the node and the previous hop node are at the intersection,the Cross Node Judgement Algorithm(CNJA)uses the angle weight judgment method and the distance weight judgment method.The algorithm judges whether the current node is suitable for forwarding the interest packet based on the weight of the angle between the connection between the node and the target node and the connection between the previous hop node and the target node and the distance to the target node.The forwarding model also sets interest packet forwarding wait mechanism and interest packet storage retransmission mechanism to ensure the reliability of the interest packet propagation.The dynamic broadcasting mechanism of the NEWBEACON packet sets different transmission periods through the speed of the vehicle nodes to ensure the timeliness of information exchange between neighboring nodes.In order to perform performance detection on the proposed data forwardingmodel,a Bonnmotion trajectory generation tool is first used to generate a moving track file for a vehicle node.The NS-3 simulation platform used then simulates the forwarding strategy and other comparative forwarding strategies to simulate the communication between vehicles and the trajectory of the vehicle.By analyzing the results of comparative experiments,we can see that compared with the existing forwarding strategies,the location-based forwarding model proposed in this paper can improve the packet hit rate,reduce the average delay,and can be better applied to the communication between vehicles.By analyzing the results of comparative experiments,we can see that compared with the existing forwarding strategies,the location-based forwarding model proposed in this paper can improve the packet hit rate,reduce the average delay,and can be better applied to the communication between vehicles.