基于区块链的医疗大数据安全存储管理研究

This project focuses on the research direction "Medical Health Theories and Methods Based on Big Data" in the guide, focusing on the data island problem, information loss problem and privacy disclosure problem that urgently need to be solved in the management of medical big data, this project researches the key theories and methods of medical big data secure storage management based on blockchain technology to realize practicability and controllability, as well as enhance anonymity and security. First of all, the consortium blockchain, combined with the election system and super ledger, is used to build a practical healthchain that collects the data of different medical service institutions. Secondly, smart contracts and consensus mechanisms are used to establish a trusted execution-consensus-update structure. Using hash algorithm and multi-recipient public key searchable encryption technology, a trusted management and control scheme for medical big data storage is proposed. Thirdly, the public key cryptography protocol for medical big data information authentication is designed by using lattice basis delegation algorithm. A completely anonymous post-quantum blockchain scheme is constructed by using the principle of rejection sampling and ring signature algorithm to enhance the anonymity of medical big data. Finally, based on the theory of lattice cryptography, a fine-grained access control trapdoor for medical big data is set up. Using the Gaussian preimage sampling algorithm, combined with the data attribute security access strategy, a post-quantum attribute encryption scheme for medical big data management is proposed to enhance the security of medical big data against quantum computing attacks.

本项目关注指南中研究方向“基于大数据的医疗健康理论与方法”，重点抓住医疗大数据管理中亟需解决的数据孤岛、信息丢失与隐私泄露问题，利用区块链技术，对医疗大数据安全存储管理的关键理论与技术进行研究，实现实用性与可控性，增强隐匿性与安全性。首先，利用联盟链，结合选举制度与超级账本，构建出汇集不同医疗服务机构数据的实用型健康链。其次，利用智能合约与共识机制，建立可信执行—共识—更新架构。采用哈希算法与多接收者公钥可搜索加密技术，提出医疗大数据存储可信管控方案。再次，利用格基派生算法，设计医疗大数据信息认证公钥密码协议。利用拒绝采样原理与环签名算法，构建完全匿名的后量子区块链方案，增强医疗大数据的隐匿性。最后，基于格密码理论，设置医疗大数据细粒度访问控制陷门。利用高斯原像采样算法，结合数据属性安全访问策略，提出医疗大数据管理的后量子属性加密方案，增强医疗大数据抗量子计算攻击的安全性。

基于区块链与密码学技术，研究医疗大数据的存储与安全管理方案。在医疗数据存储管理方面，针对存储管理中的数据孤岛问题，提出了一种基于联盟链的医疗大数据安全共享与存储管理方案，该方案基于联盟链体系架构，结合区块链权益证明共识机制，依托斯坦尔博格数据资源定价博弈模型，实现了不同医疗机构间的数据共享，提高医疗大数据的效益值；针对传统中心化的数据存储系统中存在的隐私泄露与不可信等问题，提出了一种基于公钥可搜索加密的医疗大数据安全可信存储管理方案，该方案基于可搜索加密技术，为加密存储于云服务器上的医疗隐私数据生成密文索引，并将索引上链存储，利用智能合约机制，确保链上数据的安全可信存储管理。在医疗数据安全管理方面，针对安全管理中的数据隐私泄露问题，提出了一种基于盲签名的后量子区块链日志系统，该系统基于格密码体制，利用拒绝采样原理，设计了一种盲签名算法，将日志信息盲化后存储上链，保证了日志系统的盲目性与抗量子计算安全性；针对医疗大数据因恶意访问导致的安全问题，提出了一种基于属性加密的医疗大数据细粒度管理方案，该方案基于格密码体制，设计了一种属性加密算法，并设置医疗大数据细粒度访问控制陷门，实现了医疗大数据的灵活属性访问控制与细粒度管理。