关键词: 区块链, 隐私保护, 零知识证明, 身份管理, 物联网

Abstract: Distributed identity management approaches in the current IoT environment face multiple challenges such as link attacks, privacy leakage and regulatory conflicts. The plaintext attributes in verifiable credentials are easily collected, leading to the exposure of user identities. To address the above problems, a new distributed identity scheme is proposed. The scheme establishes an identity system that combines a primary identifier with multiple pseudonymous identifiers, which solves the problem of identity privacy protection. The pseudonym mechanism enhances the defense against Sybil attack, realizes the unlinked identity information, effectively reduces the risk of user identity leakage, and achieves the harmonious coexistence of privacy protection and regulation. A dual credential model is designed to combine plaintext credentials with encrypted credentials to ensure the security of sensitive attributes, chained identity data and credential links in verifiable credentials through commitment and zero-knowledge proof. Experimental analysis results show that compared with existing schemes such as Weldentity, this scheme exhibits better performance in both credential generation time and proof generation time, which fully validates its effectiveness.

Key words: blockchain, privacy protection, zero-knowledge proof, identity management, Internet of Things