A Blockchain-Based Data-Sharing Scheme for Inter-vehicular Safety Applications

Vehicular safety applications could save lives by sharing data not available from line-of-sight sensors but they also require trust among a set of mutually distrustful vehicles. We present a scheme for sharing validated vehicular trajectory data via vehicle-to-vehicle communication to help reduce traffic collisions. It does not require any centralized control or roadside infrastructure to function. Instead, vehicles share and validate data directly among each other. Our scheme combines a distributed blockchain model to create a permanent set of validated trajectory data. Vehicles join one or more consortium blockchains shared among nearby vehicles. Within each blockchain, vehicles share data between others nearby through a fully decentralized controlled flooding protocol. As blockchain and vehicular networks are prone to scalability concerns, we have designed our scheme specifically to address them. It limits the number of vehicles participating in each blockchain, bounds how widely trajectory data are shared, and organizes and merges redundant data to reduce total network traffic. We also discuss several future directions for assessing the relative performance profiles of specific blockchain and networking implementations.