RSU-based real-time data access in dynamic vehicular networks

Recently, data dissemination in vehicular networks has received considerable attention. In particular, there has been significant interest in accessing information stored at RSUs (Roadside Units). Although data access has been extensively studied in the network community, unique characteristics in vehicular networks bring us new challenges. First, the RSU provides both safety-critical and non-safety-critical services, which should be differentiated. Second, due to the limited communication range covered by RSUs, information must be provided in time to be accessed by passing vehicles. Last but not least, in a typical vehicular network, the traffic characteristics such as vehicle arrival rate, dwell time and data access pattern change from time to time, which require special efforts in information delivery to gain satisfactory performance. This paper first proposes a data dissemination framework supported by the RSU, in which an adaptable data dissemination method is presented. Next, we derive an analytical model to form the basis of performance evaluation. Last, we present a series of evaluation results to examine the system performance in dynamic traffic environments. The results not only demonstrate the effectiveness of the adaptable data dissemination mechanism, but also explore novel features of data dissemination in dynamic vehicular networks, which give insights into new research problems.