A Rational Secret Sharing Protocol with Unconditional Security in the Synchronous Setting

In order to realize unconditionally secure rational secret sharing over a synchronous (non-simultaneous) channel, previous works either rely on the existence of honest players or induce the approximate notion of e-Nash equilibrium. In this paper, we design two rational t-out-of-n secret sharing protocols for \(t<\lceil\frac{n}{3}\rceil\) and \(t<\lceil\frac{n}{2}\rceil\) respectively, which achieve unconditional security and run in the synchronous setting without requiring any honest player. The former protocol is based on the use of verifiable secret sharing, and the latter protocol extends the former one by using the information checking protocol. Moreover, both of our protocols achieve an enhanced notion of \(\mathcal{C}\) -resilient strict Nash equilibrium (\(\mathcal{C}\) consists of the coalitions of less than t players), which guarantees that the prescribed strategy is the only best response even for colluding players, and is stronger than e-Nash equilibrium.

[1]  Kyung-Hyune Rhee,et al.  Information Security and Cryptology - ICISC 2010 , 2010, Lecture Notes in Computer Science.

[2]  David C. Parkes,et al.  Fairness with an Honest Minority and a Rational Majority , 2009, TCC.

[3]  Joseph Y. Halpern,et al.  Rational secret sharing and multiparty computation: extended abstract , 2004, STOC '04.

[4]  C. Pandu Rangan,et al.  Information Theoretic Security , 2011, Lecture Notes in Computer Science.

[5]  C. Pandu Rangan,et al.  Rational Secret Sharing with Honest Players over an Asynchronous Channel , 2011, IACR Cryptol. ePrint Arch..

[6]  Yun Zhang,et al.  An Efficient Rational Secret Sharing Scheme Based on the Chinese Remainder Theorem , 2011, ACISP.

[7]  Cynthia Dwork,et al.  Advances in Cryptology – CRYPTO 2020: 40th Annual International Cryptology Conference, CRYPTO 2020, Santa Barbara, CA, USA, August 17–21, 2020, Proceedings, Part III , 2020, Annual International Cryptology Conference.

[8]  Tal Rabin,et al.  Verifiable secret sharing and multiparty protocols with honest majority , 1989, STOC '89.

[9]  Joseph Y. Halpern,et al.  A Computational Game Theoretic Framework for Cryptography , 2009 .

[10]  Danny Dolev,et al.  Distributed computing meets game theory: robust mechanisms for rational secret sharing and multiparty computation , 2006, PODC '06.

[11]  Avi Wigderson,et al.  Completeness theorems for non-cryptographic fault-tolerant distributed computation , 1988, STOC '88.

[12]  Georg Fuchsbauer,et al.  Efficient Rational Secret Sharing in Standard Communication Networks , 2010, IACR Cryptol. ePrint Arch..

[13]  Bart Preneel,et al.  Advances in cryptology - EUROCRYPT 2000 : International Conference on the Theory and Application of Cryptographic Techniques, Bruges, Belgium, May 14-18, 2000 : proceedings , 2000 .

[14]  Information Security and Privacy , 1996, Lecture Notes in Computer Science.

[15]  Moni Naor,et al.  Games for exchanging information , 2008, STOC.

[16]  Shai Halevi Advances in Cryptology - CRYPTO 2009, 29th Annual International Cryptology Conference, Santa Barbara, CA, USA, August 16-20, 2009. Proceedings , 2009, CRYPTO.

[17]  Yehuda Lindell,et al.  Utility Dependence in Correct and Fair Rational Secret Sharing , 2009, CRYPTO.

[18]  Zhifang Zhang,et al.  Unconditionally Secure Rational Secret Sharing in Standard Communication Networks , 2010, ICISC.

[19]  Anna Lysyanskaya,et al.  Rationality and Adversarial Behavior in Multi-party Computation , 2006, CRYPTO.

[20]  Jonathan Katz,et al.  Rational Secret Sharing, Revisited , 2006, SCN.

[21]  Ueli Maurer,et al.  General Secure Multi-party Computation from any Linear Secret-Sharing Scheme , 2000, EUROCRYPT.