User Authentication Algorithm Guaranteeing Reusability of Biometric Data in BioPKI System

The PKI system performs mutual authentication, using the private and public keys published by the Certificate Authority. In this system, private keys are protected with a password. Therefore, it has password leak vulnerability. To improve conventional password-based authentication vulnerability, there have been a lot of studies on biometric data-based authentication technologies these days. The BioPKI system in which biometric data authentication technology is applied to the conventional PKI system enables user authentication and digital signature, using the biometric data-based authenticated certificate. However, the biggest problem of this biometric data authentication technology is that once exposed to an attacker, it wouldn’t be valid anymore. And concatenates the user’s fingerprint information and the fingerprint sequence number to generate a reusable Bio _FP . With the proposed method, even if the same user use the same fingerprint information it can be generated every time the other biometric data can ensure the re-usability of the end user’s fingerprint information. Therefore, this study attempted to propose a way a way to create reusable biometric data and apply it to the BioPKI system. When the proposed method was applied to the BioPKI system, attack complexity increased by approximately 1.8 × 10¹². Therefore, it can make a contribution to improving the reuse of a user’s biometric data and security in the BioPKI system.