Sciweavers

Share
EUROCRYPT
2007
Springer

Zero Knowledge and Soundness Are Symmetric

11 years 6 months ago
Zero Knowledge and Soundness Are Symmetric
We give a complexity-theoretic characterization of the class of problems in NP having zero-knowledge argument systems. This characterization is symmetric in its treatment of the zero knowledge and the soundness conditions, and thus we deduce that the class of problems in NP ∩ coNP having zero-knowledge arguments is closed under complement. Furthermore, we show that a problem in NP has a statistical zero-knowledge argument system if and only if its complement has a computational zero-knowledge proof system. What is novel about these results is that they are unconditional, i.e., do not rely on unproven complexity assumptions such as the existence of one-way functions. Our characterization of zero-knowledge arguments also enables us to prove a variety of other unconditional results about the class of problems in NP having zero-knowledge arguments, such as equivalences between honest-verifier and malicious-verifier zero knowledge, private coins and public coins, inefficient provers and...
Shien Jin Ong, Salil P. Vadhan
Added 07 Jun 2010
Updated 07 Jun 2010
Type Conference
Year 2007
Where EUROCRYPT
Authors Shien Jin Ong, Salil P. Vadhan
Comments (0)
books