Anonymous Deniable Identification in Ephemeral Setup and Leakage Scenarios (Brief Announcement)

  • Łukasz KrzywieckiEmail author
  • Mirosław Kutyłowski
  • Jakub Pezda
  • Marcin Słowik
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11527)


We present anonymous identification schemes, where a verifier can check that the user belongs to an ad-hoc group of users (just like in case of ring signatures), however a transcript of a session executed between a user and a verifier is deniable: neither the verifier nor the prover can convice a third party that a given user has been involved in a session but also he cannot prove that any user has been interacting with the verifier. Our realization of this idea is based on Schnorr identification scheme and ring signatures. We present two constructions, a simple 1-of-n case and a more advanced k-of-n, where the prover must use at least k private keys. They are immune to leakage of ephemeral keys and with minor modifications this property can be sacrificed for a simpler construction.


  1. 1.
    Krzywiecki, Ł., Kutyłowski, M., Pezda, J., Słowik, M.: Anonymous deniable identification in ephemeral setup & leakage scenarios. Cryptology ePrint Archive, Report 2019/337 (2019).
  2. 2.
    Krzywiecki, Ł., Słowik, M.: Strongly deniable identification schemes immune to prover’s and verifier’s ephemeral leakage. In: Farshim, P., Simion, E. (eds.) SecITC 2017. LNCS, vol. 10543, pp. 115–128. Springer, Cham (2017). Scholar
  3. 3.
    Naor, M.: Deniable ring authentication. In: Yung, M. (ed.) Annual International Cryptology–CRYPTO 2002 CRYPTO 2002. LNCS, vol. 2442, pp. 481–498. Springer, Heidelberg (2002). Scholar
  4. 4.
    Stinson, D.R., Wu, J.: An efficient and secure two-flow zero-knowledge identification protocol. Cryptology ePrint Archive, Report 2006/337 (2006)Google Scholar
  5. 5.
    Raimondo, M.D., Gennaro, R.: New approaches for deniable authentication. J. Cryptology 22(4), 572–615 (2009)MathSciNetCrossRefGoogle Scholar
  6. 6.
    Krzywiecki, Ł.: Schnorr-like identification scheme resistant to malicious subliminal setting of ephemeral secret. In: Bica, I., Reyhanitabar, R. (eds.) SECITC 2016. LNCS, vol. 10006, pp. 137–148. Springer, Cham (2016). Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Łukasz Krzywiecki
    • 1
    Email author
  • Mirosław Kutyłowski
    • 1
  • Jakub Pezda
    • 1
  • Marcin Słowik
    • 1
  1. 1.Department of Computer Science, Faculty of Fundamental Problems of TechnologyWrocław University of Science and TechnologyWrocławPoland

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