Study On Blockchain-Based Security Identity Authentication For Medical Cyber-Physical Systems

As the background of application in the field of health care,the flexible interaction between patients and medical system is well provided in the medical cyber-physical systems,thus realizing the omni-directional three-dimensional medical service.Physical space(including user space)and cyber space(including network space)are the basic structure of medical cyber-physical systems.Its physical basis is physical space,including all kinds of hard real-time perception health equipment,health diagnosis and treatment equipment and user space composed of various users.Cyber space is the core component of medical cyberphysical systems,which is responsible for the storage,processing and security access management of users and health information.However,a large number of users with different roles and different types of health equipment are included in the physical space,including illegal users and devices.According to the requirements of controllable and credible medical cyber-physical systems,it requires that the medical cyber-physical systems have a safe and reliable security identity authentication mechanism,so as to build a security barrier of medical cyber-physical systems.In this thesis,two key issues of medical cyber-physical systems oriented security user identity authentication and security device identity authentication are studied.Based on blockchain technology,a security authentication method for medical cyber-physical systems is proposed.The main work and innovation of this thesis are as follows:1.Based on the characteristics of blockchain,such as non tamperability and anti retroactivity,this thesis studies the decentralized security authentication protocol between users and between users,between users and services,to ensure the accuracy and efficiency of cross domain authentication and realize the security authentication between users.2.We identify the device node with multi-attribute ID and study the strict device authentication mechanism,and combine the blockchain technology to prevent malicious nodes from joining,so as to prevent the devices in the physical space from misleading and damaging the cyber space data.In order to replace the traditional trusted third-party authentication method,we build a federation chain model for blockchain nodes,which only aims at specific objects and limited third parties.At the same time,according to the analysis of the authentication scheme,the validity and feasibility of the proposed security authentication scheme are verified by using random oracle and BAN logic.