Anonymous Authorization: Privacy Engineering Toolbox

This lecture introduces the concept of anonymous authorization as a cryptographic primitive enabling users to prove possession of attributes without revealing additional information. Topics covered include zero-knowledge proofs, attribute-based credentials, and practical issues in anonymous authentication. The lecture also explores the use of blind signatures, PS credentials, and the revocation/blocking of credentials. Various credential schemes like U-Prove and Identity Mixer are discussed, along with recent developments in algebraic MACs and anonymous credentials light. The lecture concludes with discussions on constructing tokens, revocation mechanisms, and the limitations of different credential schemes.