A Lattice-Based Traceable and Direct Revocable ABPRE With Fair Verification for Data Sharing in Medical Internet of Things

With the fast-paced progress of the Medical Internet of Things (MIoT), cross-institutional data sharing has become a crucial tool for chronic disease prevention and control. Attribute-based proxy re-encryption (ABPRE) is a novel cryptographic technique that facilitates secure medical data sharing by ensuring data confidentiality and supporting fine-grained access control. However, although the existing ABPRE solution supports fine-grained access control, it still lacks an effective accountability mechanism to address a series of key issues, such as system key abuse and user revocation from shared sets. Therefore, this paper proposes a lattice-based traceable and direct revocable ABPRE with a fair verification scheme (T-DR-VABPRE) for Data Sharing in MIoT. This scheme incorporates a traceability and user revocation mechanism within the ABPRE framework, locating and depriving access rights to malicious users within a shared data set, preventing innocent users from being affected by attribute revocation. Furthermore, a trusted third party is incorporated to establish a bidirectional fair verification mechanism, verifying the correctness of proxy re-encryption results. The scheme, based on lattice problems, is inherently resistant to quantum attacks. Experimental results and performance analysis demonstrate the proposed T-DR-VABPRE scheme to be efficient and practical.