Cryptography plays a significant role in ensuring data security and confidentiality. The security provided by a crypto system mainly depends on the secrecy of the cryptographic key. If the secret key gets compromised, then it may lead to compromise of the protected data. Biometric cryptosystem provides a solution for securing the cryptographic key by binding the secret key with user biometric data. In this paper, we have proposed a novel biometric crypto system involving key binding mechanism. New objective functions have been introduced to create helper data by binding the secret key with biometric data of the user. In the retrieval phase, local minima of the objective functions act as anchors to get the secret key. Performance evaluation shows that the proposed method achieves more than 98% success rate even in presence of limited noise in the biometric data. Further, performance metrics viz., FAR, GAR, GWDR and IWDR have been obtained for cryptographic key sizes of 256, 512, 1024 and 2048 bits. Security analysis shows that the proposed method is robust against brute force attack and correlation attack.

密码学在确保数据安全性和机密性方面发挥着重要作用。密码系统提供的安全性主要取决于密码密钥的保密性。如果密钥被泄露，则可能导致受保护数据的泄露。生物识别密码系统提供了一种通过将秘密密钥与用户生物识别数据绑定来保护加密密钥的解决方案。在本文中，我们提出了一种涉及密钥绑定机制的新型生物识别密码系统。已引入新的目标功能，以通过将密钥与用户的生物特征数据绑定来创建辅助数据。在检索阶段，目标函数的局部最小值充当获取密钥的锚点。性能评估表明，即使在生物特征数据中存在有限的噪声的情况下，所提出的方法也能获得超过98％的成功率。此外，已经针对256、512、1024和2048位的密码密钥大小获得了性能度量，即FAR，GAR，GWDR和IWDR。安全分析表明，该方法具有较强的针对暴力攻击和关联攻击的能力。