Smart Contract-based Access Control Method For Internet Of Things

With the continuous development of communication technology,sensor technology and caching technology,IoT technology has gained rapid development opportunities,and a huge digital revolution has occurred at all levels of society.At present,with the diversification and isomerization of IoT products,the security issues of the IoT are becoming increasingly prominent.Under the influence of numerous unsafe factors,it is difficult to obtain a reliable guarantee for user privacy and the security of the basic network environment.Blockchain technology has emerged rapidly in recent years,which can be regarded as a distributed,time-based distributed data ledger.It utilizes technologies such as consensus protocols,modern cryptography,P2P,and smart contracts to provide a secure,stable,transparent,auditable,and low-consumption system architecture,which has retrospective,stable,and efficient security management capabilities.It provides a new solution to the identity authentication security of the Internet of Things.This paper absorbs and improves the existing access management method with blockchain as the core,and proposes a new security management method based on private chain,which solves the dynamic and intelligent access in the traditional access management method.problems such as low degree of chemicalization and high cost.This paper designs a new control and management architecture,a new capability-based access control model(Novel-Capability-Based Access Control,NCBAC).First of all,this paper abstracts the concept of management nodes,in order to solve the problems of weak computing power and low storage performance of IoT devices,which cannot meet the difficulties of direct communication between IoT devices and blockchain,and can reduce network operation overhead;secondly,it builds a multi-level In the smart contract system,three smart contracts,AC,ACC and AMC,are designed to build a credible and reliable access control entity model.The credit threshold is used to build an intelligent access rights management model for massive sensors of the Internet of Things.In the model proposed in this paper,the token mechanism is designed according to the characteristics of repeated requests in a short period of time in the real production environment of the Internet of Things system.According to the experimental results,the performance of the system is improved to a certain extent.In order to verify the usability of the scheme proposed in this paper,the function,performance and security of the whole system are tested in this paper.The experimental results show that the model constructed in this paper is feasible,safe and effective in the access control and identity authentication of the Internet of Things system.