FINGERPRINT BASED FUZZY VAULT

Abstract

Through this project we intend to create a biometrics cryptosystem where one can send and receive secure information using just the biometric features like fingerprints, signatures etc. For this purpose we have used a fingerprint based fuzzy vault technique. Reliable information security mechanisms are required to combat the rising magnitude of identity theft in our society. While cryptography is a powerful tool to achieve information security, one of the main challenges in cryptosystems is to maintain the secrecy of the cryptographic keys. Though biometric authentication can be used to ensure that only the legitimate user has access to the secret keys, a biometric system itself is vulnerable to a number of threats. A critical issue in biometric systems is to protect the template of a user which is typically stored in a database or a smart card. The fuzzy vault construct is a biometric cryptosystem that secures both the secret key and the biometric template by binding them within a cryptographic framework. We present a fully automatic implementation of the fuzzy vault scheme based on fingerprint minutiae. The 128 bit secret key used in RSA and other cryptosystems are secured with the help of fingerprint minutiae. Since the fuzzy vault stores only a transformed version of the template, aligning the query fingerprint with the template is a challenging task. We extract high curvature points derived from the fingerprint orientation field and use them to obtain an intermediate coordinate system, with the fingerprint core point as the origin. Firstly, we have explored the possibility of using the high curvature points to create an axis for the Cartesian system and then we have used that as a reference axis for polar coordinate system. Finding the core point with accuracy is in itself a very challenging task. We have proposed a new algorithm which finds the core point for all the fingerprints with complete accuracy. Thus unlike the v existing fuzzy vault implementation, we don’t need to send the helper data for aligning the query and the template minutiae, which significantly reduces the overhead whilst hiding the details of the fingerprint completely. We demonstrate the performance of the vault implementation on two different fingerprint databases.