Cryptography and Game Theory: Designing Protocols for Exchanging Information

  • Gillat Kol
  • Moni Naor
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4948)


The goal of this paper is finding fair protocols for the secret sharing and secure multiparty computation (SMPC) problems, when players are assumed to be rational.

It was observed by Halpern and Teague (STOC 2004) that protocols with bounded number of iterations are susceptible to backward induction and cannot be considered rational. Previously suggested cryptographic solutions all share the property of having an essential exponential upper bound on their running time, and hence they are also susceptible to backward induction.

Although it seems that this bound is an inherent property of every cryptography based solution, we show that this is not the case. We suggest coalition-resilient secret sharing and SMPC protocols with the property that after any sequence of iterations it is still a computational best response to follow them. Therefore, the protocols can be run any number of iterations, and are immune to backward induction.

The mean of communication assumed is a broadcast channel, and we consider both the simultaneous and non-simultaneous cases.


Nash Equilibrium Secret Sharing Secret Sharing Scheme Oblivious Transfer Exchange Step 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Gillat Kol
    • 1
  • Moni Naor
    • 1
  1. 1.Department of Computer Science and Applied MathematicsWeizmann Institute of ScienceRehovotIsrael

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