Chalkias et al. proposed zkAt, a new cryptographic primitive, in their paper, for privacy-preserving authentication on public blockchains. zkAt uses zero-knowledge proofs to allow users to authenticate transactions while keeping the underlying authentication policy private. Chalkias等人在论文中提出了零知识认证器(zkAt),一种新的密码学原语,用于在公共区块链上实现隐私保护的认证。zkAt利用零知识证明使用户能够认证交易,同时保持底层认证策略的私密性。
Notes
This paper designs a binding scenario for authentication policies, making the circuit invisible but immutable, allowing users to verify their own private policy.
Using interpolation to generate an equivalent QAP, the verification logic remains unchanged but the structure is hidden.
zkAt modifies the Groth16 setup, making the vk independent of the circuit, hiding the policy.
vk and π do not leak policy information, achieving policy privacy.
zkAt policies are fixed, updates require zkAt+.
zkAt+ uses recursive SNARKs to support privacy policy updates.