Secure and verifiable multi-keyword searchable encryption scheme in cloud

Abstract

Due to the advantages of cloud computing, such as virtualization and high scalability, individuals and enterprises are willing to outsource local data storage and computing to cloud servers.However, encryption breaks the linkability between the data.Although searchable encryption (SE) enables cloud servers to provide retrieval services of the encrypted data for data owners, cloud servers who are untrusted, may tamper and delete data, or learn information of the newly added encrypted files with previous trapdoors.Besides, single-keyword search inevitably incurs many unrelated results, resulting in a waste of bandwidth and computing resources.To address the problems above, an efficient and verifiable multi-keyword search encryption scheme was proposed, which could not only supported multiple-keyword search, but also realized the privacy of search pattern and forward security of the outsourced files.In the meanwhile, it also ensured the integrity check of the outsourced data.Through rigorous security verification, the proposed scheme was proved to be secure under the standard mode, and could resist offline keyword guesswork attack (KGA) on untrusted cloud servers.Finally, by comparing the efficiency and performance with the recent three searchable encryption schemes, the experimental results show that the proposed scheme has the best comprehensive performance in terms of function and efficiency among the four schemes.

Keywords

• cloud computing;q-ABDHE security assumption;multi-keyword search;security proof