A Privacy-Preserving Credit Bank Supervision Framework Based on Redactable Blockchain

Credit bank plays a vital role in constructing a lifelong education system. However, it confronts many security and privacy issues, and it is difficult to maintain the records. Thus, the blockchain technology has been introduced to achieve automatic management of credit bank. Unfortunately, the immutable nature of blockchain makes it impossible for students to delete their private data when they leave, which would bring data leakage risks. As an effective way to protect private data, redactable blockchain allows user to modify the data on the blockchain. However, existing redactable blockchains lack a trusted third party regulatory mechanism to ensure the legality and compliance of delete operations. To addresses these issues, based on redactable blockchain and threshold signature, this paper provides a data management scheme with privacy protection for credit bank, which supports external supervision, and allows secure and efficient deletion of student's private data on the blockchain while ensuring the privacy data of students. Theoretical analysis and experiments show that the proposed scheme can effectively resist malicious behaviors and has practical performance.