Practical Mental Poker Without a TTP Based on Homomorphic Encryption

  • Jordi Castellà-Roca
  • Josep Domingo-Ferrer
  • Andreu Riera
  • Joan Borrell
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2904)


A solution for obtaining impartial random values in on-line gambling is presented in this paper. Unlike most previous proposals, our method does not require any TTP and allows e-gambling to reach standards of fairness, security an auditability similar to those common in physical gambling.

Although our solution is detailed here for the particular case of games with reversed cards (e.g. poker), it can be easily adapted for games with open cards (e.g. blackjack) and for random draw games (e.g. keno). Thanks to the use of permutations of homomorphically encrypted cards, the protocols described have moderate computational requirements.


Mental poker E-gambling Privacy homomorphisms 


Applications of cryptography (e-gambling) Multi-party computation 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Jordi Castellà-Roca
    • 1
  • Josep Domingo-Ferrer
    • 2
  • Andreu Riera
    • 1
  • Joan Borrell
    • 3
  1. 1.Scytl Online World Security S.A.Barcelona
  2. 2.Dept. of Computer Engineering and MathsUniversitat Rovira i VirgiliTarragona
  3. 3.Dept. of Computer ScienceUniversitat Autònoma de BarcelonaBellaterra

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