Abstract / Description of output
It takes time for theoretical advances to get used in practical schemes. Anonymous credential schemes are no exception. For instance, existing schemes suited for real-world use lack formal, composable definitions, partly because they do not support straight-line extraction and rely on random oracles for their security arguments. To address this gap, we propose unlinkable redactable signatures (URS), a new building block for privacy-enhancing protocols, which we use to construct the first efficient UC-secure anonymous credential system that supports multiple issuers, selective disclosure of attributes, and pseudonyms. Our scheme is one of the first such systems for which both the size of a credential and its presentation proof are independent of the number of attributes issued in a credential. Moreover, our new credential scheme does not rely on random oracles. As an important intermediary step, we address the problem of building a functionality for a complex credential system that can cover many different features. Namely, we design a core building block for a single issuer that supports credential issuance and presentation with respect to pseudonyms and then show how to construct a full-fledged credential system with multiple issuers in a modular way. We expect this definitional approach to be of independent interest.
Original language | English |
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Title of host publication | Advances in Cryptology - ASIACRYPT 2015 - 21st International Conference on the Theory and Application of Cryptology and Information Security, Auckland, New Zealand, November 29 - December 3, 2015, Proceedings, Part II |
Pages | 262-288 |
Number of pages | 27 |
ISBN (Electronic) | 978-3-662-48800-3 |
DOIs | |
Publication status | E-pub ahead of print - 30 Dec 2015 |
Event | 21st Annual International Conference on the Theory and Application of Cryptology and Information Security - University of Auckland, Auckland, New Zealand Duration: 29 Nov 2015 → 3 Dec 2015 https://www.math.auckland.ac.nz/~sgal018/AC2015/index.html |
Conference
Conference | 21st Annual International Conference on the Theory and Application of Cryptology and Information Security |
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Abbreviated title | Asiacrypt 2015 |
Country/Territory | New Zealand |
City | Auckland |
Period | 29/11/15 → 3/12/15 |
Internet address |