Introduction: By combining blockchain technology, new technical ideas and frameworks are proposed to solve the problems related to data sharing in the construction of the national health information platform. Research on blockchain technology, propose a health chain architecture based on the alliance chain, and build a health chain platform. The new architecture can give full play to the characteristics of the alliance chain, better adapt to the development of the medical field, and can effectively solve some problems in the platform. The health chain platform can effectively solve some problems that exist on the platform, but it still needs continuous exploration and improvement.
The construction and interconnection of the national health information platform (the platform for short) is the main method for my country to realize the sharing of medical information and resources. In the construction and actual operation of the platform, it is found that the effect of data sharing and interconnection among medical institutions is not ideal, and medical data cannot It is well utilized, and there are many problems with data security and data ownership protection. The article studies the use of blockchain technology to build a national health information blockchain platform (referred to as health chain) based on the alliance chain, to solve the problems in the operation of the platform, and to provide a reference for the development of informatization in the medical industry.
1 Blockchain technology
Blockchain (Blockchain) was first proposed by Satoshi Nakamoto in the article “Bitcoin: A Peer-to-Peer Elecronic cash system”. There is no unified definition of blockchain. “China Blockchain Technology and Application Development White Paper (2016) ) “From an application perspective, blockchain technology is regarded as an innovative application model in the Internet era. It is a decentralized, open and transparent database used to store information such as transactions. It can be applied to distributed data storage, point-to-point transmission, Consensus mechanism, encryption algorithm and other computer technology fields.
1.1 Technical features Blockchain is an innovative application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm in the Internet era. Decentralization is the most basic feature of the blockchain, which means that the blockchain does not depend on the central management block, and the entire network has no centralized hardware or management organization. Blockchain technology uses consensus-based mathematical algorithms to establish a “trust” network between machines, and rely on the powerful “self-calculation capabilities” of each block to resist external attacks. The transaction process all relies on the self-control ability of the machine, which protects both parties Privacy, while increasing the security and credibility of transactions. The core of blockchain technology is to record data and contracts along the time axis, which can only be read and written, irreversible, revoked, tampered, modified and deleted. The data information in the blockchain is all stored in a chain block structure with timestamp, which can be traced back to the data information of any block, with strong traceability and verifiability.
1.2 Types of classification Block chains are divided into public chains, private chains and alliance chains according to the scope of disclosure. The public chain refers to a completely decentralized blockchain. It means that the nodes do not need any authentication mechanism, and only need to comply with the same protocol to obtain all the data on the blockchain and participate in the blockchain. Consensus mechanism. The private chain is a block chain restricted to a certain range and does not have an open authentication sharing protocol. External nodes cannot join the block chain network. The write permission of each node of the private chain is subject to internal control. The alliance chain is multi-centered and limited to the participation of alliance members. The read and write permissions and the permission to participate in accounting on the blockchain are set according to the rules of the alliance. Different nodes have different permissions. The essence is distributed custody accounting, and each node usually has a corresponding entity organization group.
2 Health chain architecture
2.1 Platform + Consortium Chain The consortium chain is the blockchain 3.0 stage, the main blockchain technology for the intelligent society, platform + consortium chain, build a health chain platform, make use of the characteristics of blockchain technology, and combine the platform’s cloud storage technology Relying on the flexible programmable features of alliance chain technology and data centers such as residents’ health records, it helps hospitals to establish and expand applications and solve the problems of imperfect development of hospital information systems, difficult integration of systems, and large heterogeneity; selective decentralization The distributed structure is applied to medical data sharing to solve the problem of insufficient infrastructure construction (a serious shortage of independent platform database server institutions and large-capacity online storage equipment institutions); the advantages of high redundancy and complex custody permissions with multiple private keys can solve the current medical Information technology security certification defects (such as CA certification or other third-party certification methods); non-tamperable timestamp features, solve data trace modification, equipment traceability and information anti-counterfeiting issues, and give full play to the technical characteristics of the alliance chain to make it suitable for medical treatment Information interconnection scenarios.
2.2 Health chain architecture The health chain system can be divided into data layer, network layer, smart contract layer, management layer, and application layer from bottom to top.
The bottom layer of the architecture is the data layer structure, which is used to store block data on the chain, private data of medical institutions, and other medical application data. The blockchain mainly uses characteristics to store data for transactions, and different databases together form a database cluster.
The network layer runs a blockchain network composed of network nodes. In this architecture, it is mainly based on the Fabric network architecture. The network is mainly composed of verification nodes VP (Verify Peer), non-verified nodes NP (Non-verified Peer), and audit nodes AP ( Alternate Peer) three types, the main function of VP is to realize the authentication function in data interaction, including the endorsement of ordinary non-verifying nodes, and the signature of transactions; NP means ordinary medical institutions and ordinary third-party institutions, which are the main producers of data interaction; AP is mainly composed of government medical departments, responsible for auditing and supervising transactions, ensuring the legitimacy of data transactions, and conducting traceability.
The smart contract layer runs the removable consensus algorithm on the blockchain, including the corresponding algorithm mechanism, data ownership, data dividends and other related agreements. These script codes are executed in the isolation sandbox.
The management operates a fair and impartial consensus mechanism for maintaining the operation of the system, a member service mechanism responsible for endorsement and identity certification, and audit services for supervision and auditing.
The application layer is a client with a visual interface implemented by a programming language. The client and the server-side business contract deployed to the on-chain code part of Fabric [3] jointly complete the application function.
Combined with the health chain architecture, the application client function of the system is realized.
In the health chain platform, patients can control their own medical and health data permissions to realize the mastery of medical data; relevant medical institutions and doctors can grasp the patient’s health data information and read it through authorization when the patient seeks a doctor; introduce safe and multi-party Computing, while fully ensuring patient privacy, through the open API interface, other untrusted third parties can also analyze and use medical health data, further increasing the utilization rate of medical health data; government departments, including the Health Commission and related The health department can use the technical features of the blockchain to be tamper-proof and traceable to accurately locate the entire flow of medical sensitive data and realize effective supervision and macro control of the national health data.
The health chain platform builds a three-tier application medical chain based on the health chain according to the type of blockchain, which are public chain, co-linked chain and private chain.
The public chain is a basic personal application chain for medical rights and interests. It represents that each node (patient) can freely join and exit the network, and participate in the reading/writing of data on the chain; the common chain is a regional hospital application, such as the medical federation Each hospital in the body is multi-center. Each hospital on the chain is a core node, and anyone else can make limited queries through open API; the private chain is the application chain within the hospital facing the terminal of each department in the hospital.
3 Conclusion
Theoretically, combined with the characteristics of the blockchain, the health chain platform can effectively solve some of the problems existing in the current platform construction and promote the sharing of medical data. However, the actual situation still needs to be implemented. At the same time, it should be aware of the limitations of this new technology and the problems that the health chain platform needs to solve, such as designing a suitable multi-party computing protocol so that the data sharing process does not reveal the original data, and establish Open medical records standards, formulate basic standards for medical services, data security, personal information protection, information sharing, etc., to ensure the data compatibility and interoperability of medical records among various institutions. It is expected that in the next few years, blockchain will bring profound changes to the medical industry. It is necessary to further actively explore its application in national health information, and explore and practice in theoretical research, top-level design, and landing models.
