Lightweight Data Sharing Scheme Based on Proxy Re-Encryption in IIoT

As cloud computing advances rapidly, Industrial Internet of Things (IIoT) devices increasingly delegate substantial amounts of data to the cloud for storage and dissemination. Before uploading data to the cloud, data owners have to encrypt it to guarantee data confidentiality in untrusted cloud environments. Due to its capacity to provide fine-grained data sharing, attribute-based encryption (ABE) is extensively used in IIoT. However, ABE decryption necessitates expensive pairing operations, which puts a significant computational strain on IIoT users with constrained resources. While traditional ABE outsourced decryption approaches can lower decryption computation overhead of the data user, they do not permit updating the access policy, and outsourced decryption results might not be accurate. In this paper, a lightweight data sharing system using proxy re-encryption (PRE) for IIoT is developed. By converting ABE ciphertext into an identity-based encryption ciphertext, flexible data sharing is implemented in addition to lowering the decryption computation cost. The correctness of the re-encrypted ciphertext is confirmed. Additionally, this approach accomplishes effective user revocation. The security of the proposed scheme is formally proven, and the computing efficiency and practicality for implementation in IIoT are confirmed by both theoretical analysis and experimental evaluation.