| Distributed generation,energy storage,electric vehicles and digital substations are becoming more and more popular in smart grid network.With the diversification of people’s needs,the devices in different regions need to work together for data sharing,mutual access and other processes.They can achieve collaborative work through the sharing of resources,services and the interaction between organizations.In the existing scheme,the computing cost of terminal access to the grid is too large,and the cross domain authentication scheme is less and inefficient.What’s worse,the storage and sharing process of smart grid data has the problems of large memory consumption and low access security.In this paper,blockchain technology is the main research direction.The characteristics and advantages of blockchain are outstanding.The non tamperability and data consistency provide security for privacy protection.Decentralized trust and data security provide ideal attributes for cross domain identity authentication process,including eliminating central failure points and ensuring reliable transaction records.Building an efficient cross domain secure communication service model for smart grid system based on blockchain technology,and ensuring the security and efficiency of grid in the process of information sharing and resource mutual access,are of great significance.Based on the above,the main contents of this paper are as follows:Firstly,we analyze the trust and trust mechanism,and study the typical Bayesian game trust evaluation scheme in this paper.We determine the weight of nodes according to the criteria of trust degree.In addition,we also study the secret sharing algorithm in secure multiparty computing(SMPC).Taking the preselected nodes in the alliance chain as the verification nodes.By taking the preselected nodes in the alliance chain as the verification nodes and learning the pbft consensus algorithm in the alliance chain,we design a weight identification signing scheme based on the idea of secret sharing.A cross domain authentication protocol is designed based on weight identification,which standardizes the access process of users to information service entities in different trust domains.The analysis shows that this scheme has high security and is more suitable for terminals with weak computing power in smart grid.Secondly,this paper studies the privacy security and cross domain identity authentication problems in the process of data interaction in smart grid system.Using ASN.1,we design the structure of weight identification.Through the research of blockchain storage mode,combining the characteristics of blockchain and cloud storage technology,this paper stores the information such as data index and address value in the blockchain and the data in the database under the cloud model.Index and address value occupy little storage space in the blockchain and reduce the load pressure of the blockchain.The analysis shows that this kind of storage mode has higher expansibility.Based on this storage mode,we design the data sharing process,and analyze the whole process of the visitor getting the target message.This paper constructs Ethereum and designs smart contracts to simulate the electricity trading process of distributed generation and load in smart grid.Through the comparative analysis of experimental simulation,the results show that when the amount of data is large,this scheme has higher storage efficiency and improves the sharing efficiency under the premise of protecting data privacy.Finally,this paper studies the access control strategy of smart grid data in the process of being shared.Based on the analysis of access control protocol and PPSPC protocol,this paper proposes a access control scheme of smart grid data based on PPSPC by combining cross domain authentication scheme with PPSPC protocol in the distribution scenario of smart grid.This paper demonstrates the privacy protection of the two stages in access control scheme.Through the experimental simulation analysis,this scheme has a good applicability for the terminals with weak communication ability in smart grid.The comprehensive performance and security of this scheme are also improved. |
