Secure data dissemination for intelligent transportation systems

Intelligent transportation systems (ITS) integrate communications and information technology into the transportation systems to provide a safer and more efficient driving experience. Transmission security is of vital importance for the deployment of ITS systems in practice. In this chapter, secure data dissemination techniques are studied for relay-assisted vehicular communications towards ITS applications. We first briefly review the state of the art of vehicular networking research. Afterwards, we investigate the secure data dissemination issues for both vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) scenarios exploiting the physical-layer security approach. For the V2I scenario, a distributed source-relay selection scheme with anti-eavesdropping capabilities is proposed, for which a source-relay pair is jointly selected to maximize the achievable secrecy rate. For the V2V scenario, a fountain-coding aided relaying scheme is developed. By using this scheme, transmission security is guaranteed as long as the legitimate receiver can accumulate the required number of fountain-coded packets before the eavesdropper does. To satisfy this condition, a constellation-rotation aided cooperative jamming method is utilized to deteriorate the received signal quality at the eavesdropper. To evaluate the performance of the proposed strategy, a novel metric called QoS violating probability (QVP) is further proposed and analyzed. Finally, in the concluding remarks, we summarize the main contributions of our work, and point out some topics that are worthy of investigation in future studies.