Decentralized Authentication and Data Access Control Scheme Using DID for Fog-Enabled Industrial Internet of Things

The Industrial Internet of Things (IIoT) integrates a wide range of devices and identities, making the protection of sensitive industrial data a critical challenge. However, existing centralized systems still face limitations such as single points of failure, inefficient identity authentication, and dependence on trusted third parties (TTPs). To address these issues, we present a blockchain-based authentication and data access control scheme for IIoT systems. The proposed scheme eliminates TTP involvement by employing decentralized identifiers (DIDs) and key-aggregate searchable encryption (KASE), utilizing scalable authentication without requiring all industrial data to be stored on the blockchain. Security robustness is demonstrated through informal analysis, the Real-or-Random (ROR) model, and the AVISPA simulation tool (v1.6). Furthermore, performance evaluation using the Multiprecision Integer and Rational Arithmetic Cryptographic Library (MIRACL) SDK shows that the proposed scheme achieves computational efficiency compared with existing solutions. Overall, the results confirm that the proposed scheme provides secure, efficient, scalable, and TTP-free data management for IIoT environments.