Anonymous Credentials: Binding Identity to Physical Authentication

This lecture discusses the concept of binding anonymous credentials to human identity through a visual authentication process. The instructor begins by differentiating between online and physical credentials, emphasizing the importance of anonymity in various applications, such as government services and COVID certificates. The lecture introduces a novel system called card-based anonymous credentials (CBAC), which minimizes data leakage and avoids storing sensitive information. The process involves issuing a card with minimal personal data, relying on human visual perception for verification. The instructor explains the cryptographic protocols involved, including the BBS Plus signature scheme, which allows for secure attribute signing without revealing personal information. The lecture also covers the roles of card issuers, credential issuers, and the security measures necessary to ensure the integrity of the system. The discussion concludes with an overview of the protocol's flow, emphasizing the importance of both the card and holder device in maintaining security and anonymity during the authentication process.