A lightweight encrypted deduplication scheme supporting backup

Keywords Ciphertext backup; Convergent encryption; Ownership modification; User revocation Abstract Data deduplication technology is frequently used by many cloud service providers to handle the exponential growth in data. To protect their data privacy, users frequently encrypt their data before uploading it to a cloud storage provider. Therefore, efficient encrypted deduplication technology has been widely studied. Although cloud storage provides convenience for users, it also has the problem of high data concentration. Once an accident occurs in the data center, the impact is enormous. Therefore, it is necessary to back up the ciphertext data after deduplication. In this paper, we propose an efficient encrypted data deduplication technology that supports backup. Our scheme uses a one-way hash chain to verify the legitimacy of a user's identity. It updates the user's ownership of the data using the user's index table. In this paper, we use the XOR operation to re-encrypt data to obtain backup ciphertext, reducing computational complexity. In LEDB, the user can extract the key from the data label. Therefore, the user does not need to manage the key separately. In addition, LEDB supports a two-level deduplication mechanism, which can not only ensure transmission security but also reduce network transmission bandwidth. Finally, LEDB allows the user to determine the integrity of the data before decrypting the ciphertext. Security analysis and experimental results show that our scheme is secure and efficient for data encryption and decryption. Author Affiliation: (a) School of Computer Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China (b) Information Engineering University, Zhengzhou 450001, China * Corresponding author. Article History: Received 8 December 2022; Revised 26 February 2023; Accepted 11 March 2023 Byline: Xinyan Wu (a), Huanwei Wang (b), Yangkai Yuan (a), Fagen Li [fagenli@uestc.edu.cn] (a,*)