Browse > Article

A1lowing Anonymity in Fair Threshold Decryption  

Kim, Jin-Il (서울대학교 전기컴퓨터공학부)
Seo, Jung-Joo (서울대학교 전기컴퓨터공학부)
Hong, Jeong-Dae (국방부)
Park, Kun-Soo (서울대학교 전기컴퓨터공학부)
Publication Information
Journal of KIISE:Computer Systems and Theory / v.37, no.6, 2010 , pp. 348-353 More about this Journal
Abstract
A threshold decryption scheme is a multi-party public key cryptosystem that allows any sufficiently large subset of participants to decrypt a ciphertext, but disallows the decryption otherwise. When performing a threshold decryption, a third party is often involved to guarantee fairness among the participants. To maintain the security of the protocol as high as possible, it is desirable to lower the level of trust and the amount of information given to the third party. In this paper, we present a threshold decryption scheme which allows the anonymity of the participants as well as the fairness by employing a semi-trusted third party (STTP) which follows the protocol properly with the exception that it keeps a record of all its intermediate computations. Our solution preserves the security and fairness of the previous scheme and reveals no information about the identities of the participants and the plaintext even though an attacker is allowed to access the storage of the STTP.
Keywords
threshold decryption; fairness; anonymity; mix-net;
Citations & Related Records
연도 인용수 순위
  • Reference
1 L. Kissner and D. Song: Privacy-preserving set operations, CRYPTO 2005, volume 3621 of Lecture Notes in Computer Science, pp.241-257, Springer-Verlag, 2005.
2 R. Cleve: Limits on the security of coin flips when half the processors are faulty(extended abstract), in STOC, pp.364-369, 1986.
3 J. Hong, J. Kim, J. Kim, M. K. Franklin, K. Park: Fair Threshold Decryption with Semi-Trusted Third Parties, in ACISP 2009, pp.309-326, 2009.
4 R. Gennaro, S. Halevi, H. Krawczyk, T. Rabin: Threshold RSA for dynamic and ad-hoc groups, In Eurocrypt 2008, LNCS, vol.4965, pp.88-107, Springer, 2008.
5 P. Fouque, G. Poupard, J. Stern: Sharing decryption in the context of voting of lotteries, Financial Cryptography 2000, 2000.
6 V. Shoup: Practical threshold signatures, In Eurocrypt 2000, 2000.
7 G. Danezis, C. Diaz: A Survey of Anonymous Communication Channels, Microsoft Technical Report MSR-TR-2008-35, 2008.
8 B. Pinkas: Fair secure two-party computation, Eurocrypt 2003, 2003.
9 J. A. Garay, P. D. MacKenzie, M. Prabhakaran, K. Yang: Resource Fairness and Composability of Cryptographic Protocols, TCC 2006.
10 D. Chaum: Untraceable electronic mail, return addresses, and digital pseudo-nyms, Communications of the ACM, 4(2), February 1982.
11 R. Gennaro, S. Jarecki, H. Krawczyk, and T. Rabin: Secure distributed key generation for discrete-log based cryptosystems, J. Cryptology, 20(1):51-83, 2007.   DOI   ScienceOn