Efficient Concurrent Zero-Knowledge in the Auxiliary String Model

  • Ivan Damgård
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1807)


We show that if any one-way function exists, then 3-round concurrent zero-knowledge arguments for all NP problems can be built in a model where a short auxiliary string with a prescribed distribution is available to the players. We also show that a wide range of known efficient proofs of knowledge using specialized assumptions can be modified to work in this model with no essential loss of efficiency. We argue that the assumptions of the model will be satisfied in many practical scenarios where public key cryptography is used, in particular our construction works given any secure public key infrastructure. Finally, we point out that in a model with preprocessing (and no auxiliary string) proposed earlier, concurrent zero-knowledge for NP can be based on any one-way function.


Commitment Scheme Probabilistic Polynomial Time Interactive Argument Intractability Assumption Cheat Prover 
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 2000

Authors and Affiliations

  • Ivan Damgård
    • 1
  1. 1.BRICS Dept. of Computer Sience, Ny MunkegadeAarhus UniversityAarhus CDenmark

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