PEACE: Privacy-Enhanced Authentication for Cryptocurrency Environments
: As blockchains gain traction in managing financial assets, robust authentication mechanisms become essential. Traditional public-private key authentication poses risks of key mismanagement, leading to significant financial losses. At the same time, in the non-blockchain context, systems like OpenID Connect (OIDC) provide user-friendly authentication with identity recovery in the traditional Web. However, they rely on a single trusted party, raising privacy concerns when applied to blockchains. In this paper, we present PEACE , an authentication mechanism for blockchains that combines the practicality of traditional Web systems with decentralization and privacy-preservation, building on a recent groundbreaking zkLogin protocol of Baldimtsi et al. (ACM CCS 2024). The protocol frees users from managing cryptographic material without giving away fund custody or relying on a single party. We detail PEACE ’s design, prove its properties in the Universal Composability framework, and present a real-world implementation compatible with existing OIDC deployments and the Ethereum blockchain.