Iranian Society of Cryptology The ISC International Journal of Information Security 2008-2045 15 3 2023 10 01 An Efficient Scheme for Secure Medical Data Sharing in the Cloud 59 66 182206 10.22042/isecure.2023.182206 EN Iman Jafarian Faculty of Computer Engineering, Amirkabir University of Technology, Tehran, Iran Siavash Khorsandi Faculty of Computer Engineering, Amirkabir University of Technology, Tehran, Iran Journal Article 2023 11 01 The Internet of Things has significantly improved healthcare with its promise of transforming technological, social, and economic perspectives. Medical devices with wireless internet access enable remote monitoring of patients, and collectively, these increasingly smart and connected medical devices can provide unique and contemporary medical and health services envisioned to be deployed in a large-scale fashion. For this, medical data and records generally are collected, stored, and shared through open-air wireless networks and public cloud infrastructures, which poses severe challenges regarding the confidentiality of sensitive medical data while maintaining low service overhead and system complexity. This paper presents a novel scheme for secure cloud-assisted Internet of Medical Things connecting patients/smart medical devices to smart applications/medical service providers in a scalable one-to-many fashion to make novel medical services practical. The proposed scheme uses index-based searchable encryption for data screening without decryption. It uses a low-overhead proxy re-encryption scheme for secure data sharing through public clouds https://www.isecure-journal.com/article_182206_c5737d73e2fea9191275643d74a551e8.pdf