Research On Supervision Technology Of Privacy Protection For Consortium Blockchain

Blockchain technology integrates various technologies such as distributed data storage,cryptography,and consensus mechanisms.With features like decentralization,programmability,tamper-proof,trustlessness and transparency,blockchain has been increasingly applied in fields such as finance and art,and has become one of the hottest research topics.However,with the development of blockchain technology,the security problems it faces are also gradually reflected.First,the completely decentralized blockchain system still lacks effective supervision methods.When attackers pose a threat to system security and illegal users use blockchain to commit illegal acts,it is difficult for the system to supervise attackers or illegal users.Lack of supervision will lead to no institution or organization willing to make credit endorsement for user data,which will breed illegal and criminal acts such as spreading bad speech and illegal fund-raising.Once violation information is recorded on the blockchain,it can spread rapidly through the consensus mechanism and can effectively evade supervision due to the data’s immutability and challenging supervision,thereby presenting significant security risks.Second,in the process of supervision,it may cause privacy disclosure.Regulators can only supervise the content when they get the plaintext of the data on the blockchain,but this may also lead to the disclosure of private data information in the blockchain.Therefore,how to better realize supervision while protecting privacy is the main problem that needs to be studied in blockchain supervision.In order to realize the supervision and privacy protection of data on blockchain,the main work of this paper is as follows:(1)Aiming at the problem that the blockchain is difficult to supervise and there is privacy leakage during supervision,this paper proposed a blockchain supervision framework that supports multi-party participation and privacy protection.The framework supports the joint supervision of multiple regulators,which can effectively avoid the problem of single point of failure.We designed a double-chain architecture to store business data and regulatory data respectively,which improved the efficiency of data processing and the scalability of blockchain.The scheme uses attribute-based encryption to realize the access control and privacy protection of data information in the blockchain,and uses attributes to correspond to the authority of the supervisor.Only the supervisor who meets the access policy in the ciphertext can participate in the supervision.Theoretical and performance analysis shows that the framework has good practicability.(2)In order to solve the problem that the authorized supervisor needs to decrypt the ciphertext of user data during blockchain supervision,and it is difficult to effectively supervise the ciphertext data,resulting in the disclosure of private data,this paper designed a blockchain supervision scheme that supports the equivalence comparison of ciphertext.Through the ciphertext equality test technology,the supervisor can realize the supervision without decrypting the data ciphertext during the supervision process,thus further realizing the privacy protection of the data information on the blockchain.In addition,when illegal information is found,the regulator can track the sender of the illegal information.Security analysis shows that the scheme can resist offline message recovery attacks.Performance analysis shows that the scheme has good practicability.