Attribute-Based Re-Encryption for Data Cloud Secure Storage and Access in End-Edge-Cloud Networks

Cloud storage can enhance the efficiency of the data storage and sharing, while it is challenge for the security of the data transmission. Attribute-Based Encryption (ABE) improves security of data sharing, but the main issues are key management and user-side computational efficiency. In this paper, an Online-Offline Re-Encryption (OORE) algorithm is proposed to improve the secure storage and access of data in cloud storage. To resolve the key management problem, we ensure that the Attribute Authority doesn't possess the user's secret key through key computation techniques. To enhance system security, we implement distinct access control strategies for users and edge routers, employing re-encryption computations. Additionally, to address the issue of prolonged pairing computation times in ABE algorithms, the proposed OORE algorithm combines online and offline encryption/decryption operations. Most complex computations are performed offline, requiring only a single pairing and a few divisions and multiplications during the online phase, thus alleviating the computational burden on users. Security analysis demonstrates that the proposed OORE algorithm can withstand chosen ciphertext attacks, affirming its security. Experimental results indicate that our algorithm effectively reduces the computational load on users while keeping ciphertext and key storage overhead within reasonable limits.