Concurrent zero-knowledge

  title={Concurrent zero-knowledge},
  author={Cynthia Dwork and Moni Naor and Amit Sahai},
  journal={IACR Cryptol. ePrint Arch.},
Concurrent executions of a zero-knowledge protocol by a single prover (with one or more verifiers) may leak information and may not be zero-knowledge <i>in toto</i>. In this article, we study the problem of maintaining zero-knowledge.We introduce the notion of an (α, β) <i>timing constraint</i>: for any two processors <i>P</i><sub>1</sub> and <i>P</i><sub>2</sub>, if <i>P</i><sub>1</sub> measures α elapsed time on its local clock and <i>P</i><sub>2</sub> measures β elapsed time on its local… 

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