Blockchain-based access control for dynamic device management in microgrid

Microgrid is a self-sufficient grid system that covers one or more kinds of distributed energy, where a variety of terminal devices collect, transmit and store electricity data based on fog-based network infrastructure. Due to security and privacy concerns, efficient and secure access control over terminal devices in microgrid is the primary way to prevent unauthorized access and data breach. Therefore, a number of solutions of device management are proposed. However, they are usually prone to single point of failure, decision-centralized, over-manual intervened. To address the problem, we introduce a blockchain-based fast and dynamic access control (FDAC) system for device management in fog-assisted microgrid. In particular, we adopt an attribute-based access control formula to model a flexible, dynamic and fast fine-grained access control system. FDAC deploys four smart contracts that dynamically manages devices, which includes user authentication, subject/object attributes, access policy, decision-making and credit assessment of user behavior. In addition, FDAC employs a Cuckoo filter to speed up policy search in smart contracts and proposes new credit verification algorithm to improve credit rewards and punishments. To clarify practical performance, we build a private blockchain platform to simulate FDAC. Compared to classic traversal approaches for policy search, FDAC maintains higher accuracy and lower time delay.