Blockchain and DID-Based Cross-Domain Identity Authentication and Maintenance in Web3

With the development and application of Web3 technology, cross-domain identity authentication and management have become crucial topics in the digital economy. However, existing cross-domain authentication methods face challenges such as low decentralization, low management efficiency, and poor interoperability. To address these issues, this paper proposes a cross-domain authentication mechanism based on Decentralized Identifiers (DID), group signatures, and dynamic accumulators, aiming to meet the security needs of cross-domain identity authentication and dynamic management in Web3. First, a consortium blockchain is constructed among different management domains. Then, a Key Generation Center (KGC) is established in each domain, responsible for jointly generating keys with users and enhancing their DIDs, thereby reducing the reliance on the KGC and increasing the level of decentralization. By improving the Verifiable Credential (VC) format through dynamic accumulators, instant verification, revocation, and permission changes are achieved, meeting the dynamic management needs in a decentralized environment. Subsequently, each management domain issues cross-domain tokens using group public keys through group signature technology, ensuring interoperability of VC tokens and user privacy protection during the identity authentication process. Finally, each management domain only needs to verify the validity of the cross-domain tokens to complete cross-domain identity authentication. The performance and experimental analysis results of this study indicate that the proposed scheme exhibits good performance and scalability.