secure smartcardbased fingerprint authentication
In this paper, the fundamental insecurities hampering a scalable, wide-spread deployment of biometric authentication are examined, and a cryptosystem capable of using fingerprint data as its key is presented. For our application, we focus on situations where a private key stored on a smartcard is used for authentication in a networked environment, and we assume an attacker can launch o -line attacks against a stolen card.Juels and Sudan's fuzzy vault is used as a starting point for building and analyzing a secure authentication scheme using fingerprints and smartcards called a figerprint vault . Fingerprint minutiae coordinates m i are encoded as elements in a nite eld F and the secret key is encoded in a polynomial f(x) over F [ x ]. The polynomial is evaluated at the minutiae locations, and the pairs ( m i , f(m i ) ) are stored along with random ( c i , d i ) cha points such that d i ? f(c i ) . Given a matching fingerprint, a valid user can seperate out enough true points from the cha points to reconstruct f(x) , and hence the original secret key.The parameters of the vault are selected such that the attacker's vault unlocking complexity is maximized, subject to zero unlocking complexity with a matching fingerprint and a reasonable amount of error. For a feature location measurement variance of 9 pixels, the optimal vault is 2 69 times more difficult to unlock for an attacker compared to a user posessing a matching fingerprint, along with approximately a 30\% chance of unlocking failure.
smartcard fingerprint authentication biometrics