A Certificateless Threshold Proxy Re-Encrypted Data-Sharing Scheme With Cloud-Chain Collaboration in Industrial Internet Environments

The industrial Internet information system has become the key to protecting the new generation of information infrastructure, and its data security storage and sharing are crucial for platform construction and alliance development. In response to security challenges, such as privacy leakage, data tampering, and lack of effective isolation in the current industrial Internet data storage and sharing process, this article proposes an industrial Internet data-sharing scheme based on multiclouds and multichains collaborative storage mode. The proposed scheme supports keyword search and utilizes certificateless threshold proxy re-encryption (PRE) technology. Our scheme allows industrial enterprises to securely store a large amount of sensitive data ciphertext in private clouds, while classifying and storing metadata ciphertext on different blockchains. A data protection algorithm that avoids private key escrow and supports ciphertext retrieval is constructed by combining certificateless PRE, threshold secret sharing, and searchable encryption techniques. In addition, a trust evaluation consensus algorithm is designed to select nodes with high trust as proxies in blockchain networks, solving the trust problem in traditional PRE schemes. Security analysis shows that our scheme can effectively resist collusion attacks and data tampering. Performance and simulation comparison analysis show that the main algorithms in our scheme have a lower time cost compared to the other typical schemes involved in comparison.