Secure data management system with traceability against internal leakage

Abstract

The management of sensitive data in an organization is not limited to use authentication and encrytion systems. Actually, malicious users inside of an organization will leak sensitive data to adversaries if the users are privileged to access to the data. In this study, we enable a manager to identify the traitor(s) inside of an organization from the leaked data. The essential technique is the fingerprinting for encrypted data. When a user decrypts a ciphertext using the secret key assigned to the user, the decrypted data involves the information associated with the user. We propose such an access control system by combining an attribute-based encryption scheme and fingerprinting scheme. The proposed method prevents a dishonest manager from framing innocent users by realizing the asymmetric protocol using the fingerprinting scheme based on a key management.