Revocable and Traceable Data Sharing and Encryption Methods in Cloud Computing Environments

Abstract

Cloud computing faces critical security challenges in permission management and leak traceability. This paper proposes a revocable and traceable data sharing scheme addressing limitations in revocation timeliness, tracking accuracy, and multi-authority collaboration. Our framework involves four components: attribute authorities for key management, public clouds for secure storage and re-encryption, data owners using binary decision tree policies for pre-encryption, and data users requiring policy compliance for decryption. Technically, we combine bilinear mapping with attribute-based encryption for fine-grained access control, optimizing performance via strategic key segmentation. Security mechanisms include key integrity verification, precise traitor tracking, and dynamic key updates with real-time ciphertext re-encryption for immediate revocation. Evaluation on a manufacturing data platform demonstrates practical effectiveness, handling 1 GB design documents with re-encryption times of 3.5–4.3 s post-permission changes. The solution maintains strong privacy, keeping information entropy below 0.20, achieving an optimal security-tracking-performance balance.