Blockchain-Based Decentralized Identity with Privacy-Preserving Biometric Authentication

Centralized traditional identity management systems present significant risks to security and privacy in the current digital world. In this paper, we introduce an innovative blockchain-based DID mechanism that incorporates state-of-the-art biometric authentication technologies. The system addresses the most significant limitations of current DID solutions, such as poor biometric integration and insecure management of keys. In this paper, we introduced the first privacy preserving protocol combining homomorphic encryption-based secure computation with blockchain for protecting storage and matching of biometric templates. The scheme employs Elliptic Cryptography (ECC) under a post-quantum cryptographic algorithm to symmetrize paradigm of secure crypts. Extensive experiment results demonstrate that under our proposed scheme, the accuracy on authentic user identity verification is 99.9%, original biometric information is fully private protected. We have built our solution on Ethereum smart contracts that are operationally tax efficient, and our average fee per transaction is 0.032 ETH. The performance investigation results are illustrated in Table 3 to indicate that our method is capable of handling a verification request of the identity about 2.3 seconds per request on average, that is quick enough for the practical application. The proposed solution heralds the advent of safe, scalable, and privacy-friendly IDM in decentralized networks.