Efficient Data Delivery Protocol Using Vehicle Mobility Information in VANETs

Vehicular Ad-hoc Networks (VANETs) have been widely recognized as a promising technology to deliver data between vehicles to support various vehicular applications such as safety driving, traffic information sharing, and infotainment service. In the environments of VANETs with a frequent network dynamic feature due to high mobility of vehicles, geographic routing is considered as an attractive approach to send data to a destination vehicle by using only the location information of vehicles. However, mobility of a destination vehicle causes a highly challenging issue for data delivery to it due to its frequent location changes according to its continuous movements. Fortunately, the future trajectory information of a destination vehicle provided by its on-board navigation system can efficiently support data delivery to it. Thus, we propose an efficient data delivery protocol using the trajectory information of a destination vehicle. The proposed protocol decides an optimal location on the trajectory of a destination vehicle by providing an arithmetical model based on a road map information to achieve the cost-minimized data. Then, to deliver data to the optimal location, the proposed protocol sends data through a route determined by considering the moving direction of the target vehicle and the forwarding direction of data. Additionally, the proposed protocol uses a trajectory-based forwarding and a redirection forwarding to cope with trajectory changes of a destination vehicle due to its moving speed and direction changes, respectively. Simulation results show that the proposed protocol is superior to a well-known geographic routing protocol, GPSR.