Published Paper Details:

Abstract: Cloud computing is a service model that provides users with the facility to store data remotely, thereby avoiding the cost and complexity of local data storage and maintenance. Numerous data integrity auditing schemes have been proposed to ensure the integrity of data stored in the cloud. In existing systems, users are required to use a private key to generate data authentication. To store this private key, users need hardware tokens (e.g., USB tokens, smart cards) and must remember a password to activate the key. If the hardware token is lost or the password is forgotten, most current data integrity auditing schemes become unusable. To overcome this limitation, we propose a new paradigm called data integrity auditing without private key storage and design a corresponding scheme. In the proposed system, biometric data (e.g., iris scan, fingerprint) is used as a fuzzy private key, eliminating the need for a hardware token. To verify user identity, a linear sketch with coding and error correction techniques is employed. Furthermore, we design a new signature scheme that supports blockless verifiability and is compatible with the linear sketch. Security proofs and performance analysis demonstrate that our proposed scheme achieves both high security and efficiency.