New guarantees for cryptographic circuits and data anonymization

Abstract

The first part of this thesis presents new definitions and constructions for three modern problems in cryptography: watermarking cryptographic circuits, updatable cryptographic circuits, and proxy reencryption. The second part is dedicate to advancing the understanding of data anonymization. We examine what it means for a data anonymization mechanism to prevent singling out in a data release, a necessary condition to be considered effectively anonymized under the European Union's General Data Protection Regulation. We also demonstrate that heretofore theoretical privacy attacks against ad-hoc privacy preserving technologies are in fact realistic and practical.