Research On Cross-domain Access Of Internet Of Things Based On Master-slave Chain

As an important part of the new generation of information technology,the Internet of Things(IoT)has been widely used in smart city,Internet of vehicles,smart medical and other fields,leading people into the era of the Internet of everything.In the context of the Internet of Everything era,the number of terminal devices of the IoT is growing exponentially,and the business objects under the IoT are developing in a diversified trend.However,due to different business objects and control methods,multiple different trust domains are often formed,and each trust domain is independent and autonomous,gradually forming the data island.At present,cross-domain access is an important solution to the problem of data island.However,under the new environment,cross-domain access mainly uses the trusted third party--cloud,fog,etc.,to complete its identity authentication.This centralized third-party authentication scheme is easy to cause single point of failure,trust crisis,and low security of private data.Blockchain technology uses distributed ledger,consensus mechanism,cryptography,smart contract and other technologies to form a decentralized distributed storage technology,make up for the shortcomings of this centralized cross-domain access scheme,and has become an important technology to solve the IoT data cross-domain access.However,due to the limitations of traditional blockchain technology,it is difficult to meet the characteristics of the large amount of data in the IoT;At the same time,the existing cross-domain access model is only for terminal devices.In the actual scenario,in order to ensure the security of data,some cross-domain access is only open for large-scale domains such as large enterprises or schools,which cannot meet the cross-domain access.In addition,there is a large amount of private data in hundreds of billions of IoT data.How to ensure the security of private data and realize its cross-domain sharing in the process of cross-domain access has become a new problem.In view of the above problems,this paper proposes a master-slave chain based cross-domain access model of the IoT,trying to solve the data island problem of the IoT,and realize cross-domain security sharing of the IoT data on the premise of ensuring the security and privacy of the IoT data.The main research work and achievements are as follows:(1)The cross-domain authentication model of the IoT based on the master-slave chain is constructed.In order to solve the data island problem of the IoT and ensure the cross-domain access of the IoT data,this paper firstly constructed the master-slave chain of the master-slave blockchain structure,and based on the master-slave chain constructed the three-layer cross-domain authentication model architecture of the IoT.At the same time,a smart contract-based intra-domain and cross-domain access mechanism is designed to realize automatic cross-domain authentication in different domains.Finally,a cross-domain security sharing scheme for private data is proposed to realize cross-domain access of private data in the IoT.Compared with the latest single-chain cross-domain model,the throughput of the proposed model is improved by about 270 TPS,and the average CPU load and average memory overhead of nodes are reduced by 24% and 64% respectively.Compared with the existing multi-chain cross-domain model,the average CPU load and average memory overhead of nodes are reduced by 15% and 20% respectively,which provides an effective method for cross-domain authentication of the IoT.(2)The cross-domain trust evaluation framework of the IoT based on domain trust is designed.The trust relationships between different trust domains must be evaluated when cross-domain access occurs between them.The application of existing trust evaluation relationships is limited to terminals.However,in actual application scenarios,domain communication partially occurs in the form of domains and the access permission is granted according to their overall trust evaluation relationship.To implement cross-domain access efficiently and safely in the form of domains and ensure the credibility of trust evaluation environment,this paper introduces the concept of domain trust,combines blockchain with domain trust,and proposes a cross-domain trust evaluation model based on blockchain and domain trust for IoT First,the system architecture of the cross-domain trust evaluation model of the IoT and network structure in the multi-domain environment are constructed according to the crossdomain access requirements of the IoT.Then,based on these,a multi-dimensional evaluation method of user node trust and domain trust is proposed.Furthermore,a cross domain access contract based on blockchain and domain trust is designed.Finally,the reliability,security,and performance of the blockchain network are analyzed and tested experimentally.The results show that,compared to BC-RBAC,the proposed model is more delicate in terms of user trust evaluation,effective prevention of time switch attack,which ensures that the trust degree of the domain is in a stable level.Compared to the Eigen Trust and Peer Trust models,the detection rate of malicious user nodes was higher by 8% and 12%,respectively,and more malicious user nodes were detected in a shorter time.Thus,the proposed method can effectively address the security concern in the evaluation of cross-domain trust in the IoT.(3)The cross-domain sharing scheme of IoT privacy data based on PURH-CPABE is proposed.This paper combines the RSA and CP-ABE algorithms to break the barriers of data islands in the IoT,achieve fine-grained access to private data,and ensure the security and flexibility of private data and access policies in cross-domain sharing.A ciphertext attribute-based encryption algorithm(PURH-CP-ABE)that supports access policy updates,cancellation,and hiding is proposed.The paper also introduces blockchain technology and proposes a private data cross-domain sharing scheme based on PURH-CP-ABE under the blockchain.In addition,the safety,function,and performance of the scheme are analyzed by theoretical proof and simulation experiments.The results show that the proposed scheme can invalidate the determination of q-PBDHE,indicating the safety thereof.Compared with HP-CP-ABE,the calculation time of the initialization,encryption,and data storage stages is reduced by 50–56% at most and 10–40% on average.The calculation time is stable during updating and revocation of the access policy.Overall,memory overhead is relatively low.Therefore,the scheme presented in this paper supports the update and withdrawal of access policies and their hiding.While ensuring the security of private data and access policies,it realizes one-to-many fine-grained cross-domain sharing of private data.In this paper,in the use of blockchain to solve the problem of data island in the IoT,the master-slave blockchain structure is redesigned to adapt to the characteristics of the large amount of data in the IoT;In order to solve the domain access problem,the TD-BCCD framework is designed by introducing the domain trust,which can satisfy the cross-domain access.At the same time,PUHR-CP-ABE algorithm is proposed to solve the security problem of private data,which realizes the cross-domain security sharing of private data,thus constructing the cross-domain access scheme of the IoT based on the master-slave chain.It provides a new research idea and technical reference for the research of blockchain cross-domain access of the IoT,which has high research significance and application value.