Identity-based authenticated multi-keyword searchable encryption scheme for cloud-assisted telemedicine information system

In cloud-assisted telemedicine information system (CA-TMIS), patients upload data containing their health metrics to the cloud. Doctors can access the patient’s data through the cloud, thereby alleviating the geographical restrictions in the traditional medical system. To ensure the privacy of the patient, the patient will encrypt the data before uploading the data. How doctors can search through numerous encrypted files to locate specific patients’ relevant data is a topic worthy of research. Searchable encryption technology can fulfill the function of ciphertext retrieval. Some existing searchable encryption schemes use single-keyword for searching, resulting in insufficient search accuracy and increased search costs for doctors. Multi-keyword searchable encryption schemes can address this issue. Therefore, in this paper, we propose an identity-based authenticated multi-keyword searchable encryption scheme, which leverages multiple keywords for combined searching, enhancing search accuracy. The scheme is proven to be resistant to keyword guessing attacks in the standard model. Compared to four other existing schemes, our scheme does not utilize pairing operations and offers higher efficiency advantages. Consequently, our scheme is more suitable for CA-TMIS.