Abstract: To solve the problems of data leakage and data silos between medical institutions in medical system, a SM9based decentration crosschain medical data sharing scheme (DCCMDSS) is proposed in this article. Relay chain and hash time lock contract (HTLC) realize the crosschain data sharing between medical institutions, the interplanetary file system (IPFS) reduces the storage pressure of blockchain and ensures the integrity of medical data. SM9based algorithm encrypts medical data and group signature allows the group members to sign the data on behalf of the whole group without revealing their personal identities. Consequently, DCCMDSS effectively avoids the privacy leakage and ensures the traceability of signature. DCCMDSS reduces the crosschain transaction overhead and improves the security of medical data.

Key words: SM9 algorithm, medical data sharing, consortium blockchain, crosschain protocol, group signature

摘要： 为了解决医疗系统中数据泄露和医疗机构间数据的孤岛问题，提出基于国密SM9的去中心化跨链医疗数据共享方案(SM9based decentration crosschain medical data sharing scheme, DCCMDSS).中继链和哈希时间锁定合约实现了医疗机构之间跨链数据的可信共享，星际文件系统存储模式降低了区块链的存储压力并确保了医疗数据的完整性.SM9用于加密医疗数据，群签名允许群体成员代表集体签署数据而无需暴露个人身份，有效避免了隐私泄露问题并保证了签名的可追溯性.DCCMDSS降低了跨链交互中的计算复杂度，提升了医疗数据的安全性.

关键词: SM9算法, 医疗数据共享, 联盟链, 跨链协议, 群签名