基于多层次区块链的医疗数据共享模型

Multi-level blockchain-based model for medical data sharing

基于区块链的医疗数据共享能够有效地提升医疗数据的可信性,但是面临着链上存储容量有限、缺乏数据隐私保护等问题。针对这些问题,提出一个基于多层次区块链的医疗数据共享模型。对个人医疗数据进行加密后上传到链下的分布式存储中,并将数据索引信息上传到链上,利用多层次区块链协同技术和链上链下混合存储方式提高存储效率;引入差分隐私保护联邦学习中模型参数提升数据的隐私安全。实验结果表明,相对于以太坊而言,该方案机构存储开销平均下降了60%左右,用户存储开销平均下降30%左右。

Blockchain-based medical data sharing method can effectively enhance the credibility of medical data.However,the limitation of storage capacity on blockchains and the lack of privacy protection in data have restricted the development of medical blockchains.This paper introduced a multi-level blockchain-based model for medical data sharing.Through encrypting personal medical data and their index information,it uploaded the encrypted data to the off-chain distributed storage and on-chain storage respectively.By utilizing both on-chain and off-chain hybrid storage technology and multilevel blockchains,the model improved the efficiency of data storage obviously.Moreover,the model enhanced the protection of data privacy by employing differential privacy technique in transferring parameters of federated learning module.The experimental result of the model demonstrates that the storage costs on the institution side are reduced by about 60%,and the storage costs on the user side are reduced by about 30% on average in comparison with Ethereum.