Multibiometric Template Security Using Fuzzy Vault

Template security is a critical issue in biometric systems because biometric templates cannot be easily revoked and reissued. While multibiometric systems overcome limitations such as non-universality and high error rates that affect unibiometric systems, they require storage of multiple templates for the same user. Securing the different templates of a user separately is not optimal in terms of security. Hence, we propose a scheme for securing multiple templates of a user as a single entity. We derive a single multibiometric template from the individual templates and secure it using the fuzzy vault framework. We demonstrate that a multibiometric vault provides better recognition performance and higher security compared to a unibiometric vault. For example, our multibiometric vault based on fingerprint and iris achieves a GAR of 98.2% at a FAR of ap 0.01%, while the corresponding GAR values of the individual iris and fingerprint vaults are 88% and 78.8%, respectively. Further, we also show that the security of the system is only 41 bits when the iris and fingerprint vaults are stored separately. On the other hand, the multibiometric vault based on fingerprint and iris provides 49 bits of security.