As an emerging paradigm in digital identity, Decentralized Identity (DID) appears advantages over traditional identity management methods in a variety of aspects, e.g., enhancing user-centric online services and ensuring complete user autonomy and control. Verifiable Credential (VC) techniques are used to facilitate decentralized DID-based access control across multiple entities. However, existing DID schemes generally rely on a distributed public key infrastructure that also causes challenges, such as context information deduction, key exposure, and issuer data leakage. To address the issues above, this paper proposes a issuer-hiding and privacy-preserving DID multi-party authentication model with a signature-less VC scheme, named SLVC-DIDA, for the first time. Our proposed scheme avoids the dependence on signing keys by employing hashing and issuer membership proofs, which supports universal zero-knowledge multi-party DID authentications, eliminating additional technical integrations. We adopt a novel zero-knowledge circuit to maintain the anonymity of the issuer set, thereby enabling public verification while safeguarding the privacy of identity attributes via a Merkle tree-based VC list. Furthermore, by eliminating reliance on a Public Key Infrastructure (PKI), SLVC-DIDA enables decentralized and self-sovereign DID authentication. Our experiments further evaluate the effectiveness and practicality of SLVC-DIDA.

翻译：作为数字身份领域的新兴范式，去中心化身份相较于传统身份管理方法在多个方面展现出优势，例如增强以用户为中心的在线服务并确保用户完全自主与控制。可验证凭证技术被用于促进跨多个实体的去中心化DID访问控制。然而，现有DID方案通常依赖于分布式公钥基础设施，这也带来了上下文信息推断、密钥暴露和发行方数据泄露等挑战。为解决上述问题，本文首次提出了一种采用无签名VC方案的发行方隐藏且隐私保护的DID多方认证模型，命名为SLVC-DIDA。我们提出的方案通过采用哈希与发行方成员证明来避免对签名密钥的依赖，支持通用的零知识多方DID认证，无需额外技术集成。我们采用一种新颖的零知识电路来维护发行方集合的匿名性，从而在通过基于Merkle树的VC列表保护身份属性隐私的同时实现公开验证。此外，通过消除对公钥基础设施的依赖，SLVC-DIDA实现了去中心化且自主主权的DID认证。我们的实验进一步评估了SLVC-DIDA的有效性与实用性。