Privacy-Preserving Multi-Keyword Searchable Encryption for Distributed Systems

• Published in: IEEE transactions on parallel and distributed systems Vol. 32; no. 3; pp. 561 - 574
• Main Authors: Liu, Xueqiao, Yang, Guomin, Susilo, Willy, Tonien, Joseph, Liu, Ximeng, Shen, Jian
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: access pattern; Algorithms; Cloud computing; Computer architecture; Computer networks; Data privacy; Data search; Data storage; Encryption; Keyword search; Keywords; multi-keyword search; multi-user access; Privacy; Public key; search pattern; Searchable encryption; Servers
• DOI: 10.1109/TPDS.2020.3027003
• ISSN: 1045-9219

As cloud storage has been widely adopted in various applications, how to protect data privacy while allowing efficient data search and retrieval in a distributed environment remains a challenging research problem. Existing searchable encryption schemes are still inadequate on desired functionality and security/privacy perspectives. Specifically, supporting multi-keyword search under the multi-user setting, hiding search pattern and access pattern, and resisting keyword guessing attacks (KGA) are the most challenging tasks. In this article, we present a new searchable encryption scheme that addresses the above problems simultaneously, which makes it practical to be adopted in distributed systems. It not only enables multi-keyword search over encrypted data under a multi-writer/multi-reader setting but also guarantees the data and search pattern privacy. To prevent KGA, our scheme adopts a multi-server architecture, which accelerates search response, shares the workload, and lowers the key leakage risk by allowing only authorized servers to jointly test whether a search token matches a stored ciphertext. A novel subset decision mechanism is also designed as the core technique underlying our scheme and can be further used in applications other than keyword search. Finally, we prove the security and evaluate the computational and communication efficiency of our scheme to demonstrate its practicality.