Concurrent Zero-Knowledge With Registered Public-Keys

ZHAO Yunlei 
Fudan University

Friday, March 19, 2004.
11-12, room 3464



Abstract
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Zero-knowledge is firstly introduced by Goldwasser, Micali and Rackoff to 
illustate situations in which a knowledge prover reveals nothing other than 
the verity of the statement to an even  malicious verifier. 
Since its introduction, zero-knowledge has been proven to be a very powerful 
tool in both cryptography and theoretical computer science (such as complexity 
theory and approximation algorithms) and  plays now the central role in modern 
cryptography.

With the far and wide popularity of Internet, more recent research attention 
has been extensively paind to the  security threats of zero-knowledge 
protocols when they are concurrently executed over Internet. In such 
concurrent setting, there are three kinds of security threats to be 
considered: Concurrent prover security (concurrent zero-knowledge), concurrent 
verifier security (concurrent soundness) and concurrent channel security 
(concurrent non-malleability).
In this talk we will briefly discuss how to construct zero-knowledge protocols 
that satisfies all the bove three kinds of security properties. These results 
stand for the current state-of-the-art of concurrent zero-knowledge in the 
literature.