PECD-DSIIoT: Privacy-enhanced cross-domain data sharing scheme for IIoT

With the rapid development of the Industrial Internet of Things (IIoT) under emerging manufacturing paradigms, the demand for cross-domain data interaction has significantly increased. However, challenges related to cross-domain trust management and data privacy protection remain key obstacles to achieving efficient data sharing. Existing solutions primarily focus on identity authentication and data sharing within a single management domain. The limited number of cross-domain approaches available tend to either emphasize authentication alone or adopt a single-chain architecture, which fails to meet the complex trust requirements in IIoT environments. To address these challenges, we propose a Privacy-Enhanced Cross-Domain Data Sharing Scheme for IIoT (PECD-DSIIoT). First, the proposed scheme adopts a dual-chain architecture that integrates a consortium blockchain and a private blockchain, enabling secure and controlled cross-domain data sharing. In this architecture, the consortium blockchain is responsible for cross-domain identity authentication, ensuring secure authentication across different management domains, while the private blockchain is used for storing sensitive data, enabling controlled data sharing. Additionally, the scheme employs an attribute obfuscation function to conceal access policies, preventing the exposure of access control rules. A verifiable pre-decryption mechanism is incorporated to ensure the integrity and correctness of data before decryption. Moreover, a non-interactive zero-knowledge proof is used to enable privacy-preserving identity authentication. Finally, a hybrid on-chain and off-chain storage strategy is adopted to alleviate blockchain storage overhead. Theoretical analysis and experimental results demonstrate that the proposed scheme not only enhances system security and privacy protection but also achieves low computational overhead and efficient data sharing, making it a highly feasible and practical solution.