Fog-Aided Verifiable Privacy Preserving Access Control for Latency-Sensitive Data Sharing in Vehicular Cloud Computing

VCC is an emerging computing paradigm developed for providing various services to vehicle drivers, and has attracted more and more attention from researchers and practitioners over the last few years. However, privacy preserving and secure data sharing has become a very challenging and important issue in VCC. Unfortunately, existing secure access control schemes consume too many computation resources, which prevents them from being performed on computing resource constrained vehicle onboard devices. Also, these cloud-based schemes suffer large latency and jitter due to their centralized resource management, and thus may not be suitable for real-time applications in VANETs. In this article, we thus propose a novel fog-to-cloud-based architecture for data sharing in VCC. Our scheme is a cryptography-based mechanism that conducts fine-grained access control. In our design, the complicated computation burden is securely out-sourced to fog and cloud servers with confidentiality and privacy preservation. Meanwhile, with the prediction of a vehicle's mobility, pre-pushing data to specific fog servers can further reduce response latency with no need to consume more resources of the fog server. In addition, with the assumption of no collusion between different providers for the cloud and fog servers, our scheme can provide verifiable auditing of fog servers' reports. The scheme is proved secure against existing adversaries and newborn security threats. Experimental test shows significant performance improvement in edge devices' overhead saving and response delay reduction.