A Consortium Blockchain System Designed For Supervision Purposes

In recent years,blockchain has been widely used in many real-world scenarios due to its characteristics such as immutability and openness.However,these characteristics have also led to some problems.The immutability of blockchain makes it difficult to change once illegal or private data is on the chain,which can have lasting negative impacts on the blockchain.individuals,and businesses.The openness of blockchain means that all participants have access to the data,creating the risk of privacy breaches.In order to promote the healthy development of blockchain,research on the regulation and security of blockchain technology and its applications has become an industry consensus.Different research teams have proposed redactable blockchain and blockchain-based access control schemes to address data security and privacy leakage issues.However,the lack of the solution combining with supervision has made it difficult to define regulators’ editing rights and access permissions in practical applications.Additionally,there is a lack of solutions that simultaneously allow for on-chain data editing and access control,which means that when the sensitivity level of on-chain data changes,the access policies cannot be updated accordingly,and the risk of data privacy leakage still exists.This paper proposes a consortium blockchain system designed for supervision using technologies such as chameleon hash functions and multi-authority attribute-based encryption.The system aims to address data security and privacy leakage issues while accelerating the application of consortium chain.The main contributions can be summarized as follows:(1)A redactable blockchain scheme for consortium chains is proposed to address the security issues arising from immutability.The solution utilizes chameleon hash functions to design the underlying structure of the blockchain,and editing rights are distributed by the regulatory authority to regulators.Different transaction types are designed,including the record transaction and change transaction,which record the editing behavior of the regulators and the edited version of the transactions to ensure the legitimacy of regulators’ behavior.(2)An access control scheme for consortium chains is proposed to address the privacy leakage issues arising from openness.The solution utilizes multi-authority attribute-based encryption to design an access control module.The regulatory authority completes the global setting including the setting of global parameters and the supervision policy,while other organizations generate a pair of public and private keys to act as authorities and generate attribute private keys for all users belonging to them,realizing decentralization and avoiding the problem of excessive authority of a single node.The module is relatively independent of the blockchain,so it has a pluggable feature.(3)A consortium blockchain system designed for supervision purpose based on the Tendermint framework,the React front-end framework and the Django back-end framework is implemented.The system supports data owners sending data encrypted with attributes,supports regulators viewing private data and editing on-chain data,and meets the update needs of the access policies of the on-chain ciphertext.It also supports regulators and other users of the consortium blockchain using the front-end interface.Test results show that the system meets expectations,allowing regulators to modify and access on-chain data while ensuring data security and privacy,and its performance meets usage requirements.It has good application value and prospects.