A Scalable Mechanism of Cloud Storage for Data Integrity Auditing without Private Key Storage

Abstract

Many data integrity auditing systems are proposed to ensure the integrity of the information
stored in the cloud. A user's private key is typically required to obtain the information authenticators needed for
information integrity auditing in most, if not all, current schemes. In order to use this private key, the user must
have a hardware token to store his private key and remember a password. Most current data integrity auditing
systems are unable to determine if this hardware token or password has been lost or forgotten. For this reason,
we suggest a new paradigm termed data integrity auditing that does away with the need for private key storage
altogether. To avoid requiring a hardware token, we employ biometric data because the user's private key is
fuzzy. In the meanwhile, the system is still capable of successfully completing the audit of information integrity.
We validate the user's identification using a linear sketch with coding and error correction methods. Additional
to this, we design a substitute signature scheme that is not only blockless verifiable, but is also compatible with
the linear sketch.