A Dual Auditing Scheme of Cross-Chain Data Shared Among the Blockchain Network

The demand for blockchain-based data storage and interaction is increasing substantially. Cross-chain technology has alleviated the isolation between different chains in currency transactions. However, in fields like the Internet of Things, cross-chain data sharing security has gained significant attention. The main challenge in data sharing is ensuring data integrity, consistency, and privacy. Therefore, auditing data integrity across chains is crucial. Current research primarily focuses on the cross-chain interaction of individual data, neglecting data source auditing and resulting in an incomplete shared data auditing scheme. Additionally, on-chain blockchain transactions have limited storage space and transaction processing speed. Identifying duplicate data and rejecting duplicate transaction uploads is essential in this context. Furthermore, in most blockchain applications, efficient handling of dynamic data is crucial due to the frequent updates in the dataset. Consequently, to check the correctness of data sources, ensure the integrity and consistency of cross-chain data, and achieve data dynamism and privacy, we design a dual-audit scheme for cross-chain shared data. The designed scheme utilizes the core idea of governing the chain by chain for decentralized audit, the message-locked encryption for data privacy and duplicate data identification, an improved Merkle tree for efficient batch addition of dynamic data, smart contracts for dual-audit algorithm, identity-based public key cryptography and the homomorphic tag algorithm for reducing on-chain computation overhead. Security analysis proves the scheme to be secure in the threat model. Experimental results demonstrate that our dual-audit scheme achieves high efficiency in terms of time overhead and communication costs.