Design And Implementation Of Internet Of Things Access Control System Based On Blockchain

The combination of blockchain technology and Internet of Things access control to solve the problem of single point of failure and achieve decentralized access control is the current research trend of Internet of Things access control.This thesis designs and implements a blockchain-based access control system for the Internet of Things,which uses smart contract technology in the blockchain to make access control decisions.Access control permissions only flow between the user and the blockchain to ensure reliability of access control.This thesis designs an access control policy model FACPM(Fabric Access Control Policy Model)to solve the problems of unauthorized access and over-authorization in the access control based on blockchain because of the coarse granularity of access control policy.The model can achieve finegrained access control by checking the attributes of users who apply for access control rights through the cooperation of multiple sub-elements.Because the data in the blockchain is transparent to the participating blockchain nodes,when using the blockchain to store the access control policy,the relevant information will be exposed to all nodes,resulting in the user's sensitive information being illegally obtained by others.This thesis designs an access control policy protection scheme FACPPS(Fabric Access Control Policy Protection Scheme),which stores the access control policy information and other data in different blockchains without affecting the access control process,thus,protecting the integrity and privacy of the access control policy information.This thesis chooses Hyperledger as the blockchain architecture,and uses fabricsdk-node to implement the application of the system on Ubuntu platform.The function and performance of the system are tested.The test results show that compared with the same type of research,the proposed system in this thesis has better performance in data writing and can withstand more large-scale access requests.Finally,the application test of the system in the smart home scene shows that the system has practical value.