Blockchain-Based Key Aggregation for Searchable Encryption in the IOMT

The extensive use of Internet of Medical Things (IoMT) devices has greatly broadened both the range and volume of data gathered, driving the rapid emergence of smart healthcare and personalized medicine. Through wearable medical devices, users can collect and share personal health data in real time. However, if these sensitive health data are leaked or misused, they can severely impact users' privacy and quality of life. To address the challenges faced by current health data sharing, this paper introduces a blockchain-based scheme for key aggregate searchable encryption. The proposed scheme leverages key aggregate searchable encryption technology to not only achieve efficient ciphertext data search but also solve key management and transmission problems. Furthermore, by utilizing blockchain and smart contract technology, the scheme supports public verification and fair payment features. The decentralized and distributed architecture of IPFS is used to reduce the risk of single-point failure, enhance system reliability, reduce network latency and bandwidth requirements, and improve real-time data processing efficiency and user experience. Finally, this paper concludes with security analysis and simulations, demonstrating that the scheme supports secure and adaptable health data sharing.