This seminar presents our research on anonymous credentials with Publicly Auditable Privacy Revocation (PAPR). PAPR credentials simultaneously provide conditional user privacy and auditable privacy revocation for credential systems. The first property implies that users keep their identity private when authenticating unless and until an appointed authority requests to revoke this privacy, retroactively. The second property enforces that the auditors can verify whether or not this authority has revoked privacy from an issued credential (i.e. learned the identity of the user who owns that credential), holding the authority accountable. In other words, the second property enriches privacy revocation for anonymous credentials with transparency by design, effectively discouraging such systems from being used for mass surveillance.
Joakim Brorsson is a PhD student at Lund University, co-supervised by Elena Pagnin at Chalmers University. His research interests lie in security and cryptographic methods to reduce trust in third parties.