Biometric Template Security

Biometric recognition offers a reliable and natural solution to the problem of user authentication in identity management systems. With the widespread deployment of biometric systems in various applications, there are increasing concerns about the security and privacy of biometric technology. Public confidence and acceptance of the biometrics technology will depend on the ability of system designers to demonstrate that these systems are robust, have low error rates and are tamper proof. We present a high-level categorization of the various vulnerabilities of a biometric system and discuss countermeasures that have been proposed to address these vulnerabilities. In particular, we focus on biometric template security which is an important issue because unlike passwords and tokens, compromised biometric templates cannot be revoked and reissued. Due to intra-user variability in the acquired biometric traits, ensuring the security of the template while maintaining the recognition performance is a challenging task. We present an overview of various biometric template protection schemes and discuss their advantages and limitations in terms of security, revocability and impact on matching accuracy. A template protection scheme with provable security and acceptable recognition performance has thus far remained elusive. Development of such a scheme is crucial as biometric systems are beginning to proliferate into the core physical and information infrastructure of our society.