Fully-Featured Anonymous Credentials with Reputation System Bemmann, Kai Blömer, Johannes Bobolz, Jan Bröcher, Henrik Diemert, Denis Pascal Eidens, Fabian Eilers, Lukas Haltermann, Jan Frederik Juhnke, Jakob Otour, Burhan Porzenheim, Laurens Alexander Pukrop, Simon Schilling, Erik Schlichtig, Michael Stienemeier, Marcel ddc:000 We present CLARC (Cryptographic Library for Anonymous Reputation and Credentials), an anonymous credentials system (ACS) combined with an anonymous reputation system. Using CLARC, users can receive attribute-based credentials from issuers. They can efficiently prove that their credentials satisfy complex (access) policies in a privacy-preserving way. This implements anonymous access control with complex policies. Furthermore, CLARC is the first ACS that is combined with an anonymous reputation system where users can anonymously rate services. A user who gets access to a service via a credential, also anonymously receives a review token to rate the service. If a user creates more than a single rating, this can be detected by anyone, preventing users from spamming ratings to sway public opinion. To evaluate feasibility of our construction, we present an open-source prototype implementation. ACM 2018 info:eu-repo/semantics/conferenceObject doc-type:conferenceObject text http://purl.org/coar/resource_type/c_5794 https://ris.uni-paderborn.de/record/3265 Bemmann K, Blömer J, Bobolz J, et al. Fully-Featured Anonymous Credentials with Reputation System. In: <i>Proceedings of the 13th International Conference on Availability, Reliability and Security - ARES ’18</i>. New York, NY, USA: ACM. doi:<a href="https://doi.org/10.1145/3230833.3234517">10.1145/3230833.3234517</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1145/3230833.3234517 info:eu-repo/semantics/altIdentifier/isbn/978-1-4503-6448-5 info:eu-repo/semantics/openAccess