Witness hiding is a property attributed to an interactive proof or an interactive argument, similar in nature to the zero-knowledge property. If an interactive proof is zero-knowledge, it is also witness hiding, but the converse does not necessarily hold. For many applications, witness hiding protocols are sufficiently secure and more efficient than zero-knowledge protocols.
Loosely speaking, an interactive proof is witness hiding if an arbitrarily cheating verifier, after engaging in many executions of the protocol with an honest prover, is not able to compute a witness unless the verifier is able to compute one anyway, without interacting with the prover at all. In this context, a witness may be thought of as a private key, corresponding to a public key. If an interactive proof is witness hiding, it is not excluded that a cheating verifier learns some fraction of the bits of a witness. However, knowledge of such a fraction of the bits cannot be feasibly extended to knowing all of the...
This is a preview of subscription content, log in via an institution to check access.
References
Cramer, R., I. Damgård, and B. Schoenmakers (1994). “Proofs of partial knowledge and simplified design of witness hiding protocols.” Advances in Cryptology—CRYPTO'94, Lecture Notes in Computer Science, vol. 839, ed. Y.G. DeSnedt. Springer-Verlag, Berlin, 174–187.
Feigel, U. and A. Shamir (1990). “Witness indistinguishable and witness hiding protocols.” Proceedings of 22nd Symposium on Theory of Computing (STOC'90), ed. J.H. Silverman. ACM Press, New York, 416–426.
Goldreich, O. (2001). Foundations of Cryptography—Basic Tools. Cambridge University Press, Cambridge.
Okamoto, T. (1993). “Provably secure and practical identification schemes and corresponding signature schemes.” In Advances in Cryptology—CRYPTO'92, Lecture Notes in Computer Science, vol. 740, ed. E.F. Brickell. Springer-Verlag, Berlin, 31–53.
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2005 International Federation for Information Processing
About this entry
Cite this entry
Schoenmakers, B. (2005). Witness Hiding. In: van Tilborg, H.C.A. (eds) Encyclopedia of Cryptography and Security. Springer, Boston, MA . https://doi.org/10.1007/0-387-23483-7_461
Download citation
DOI: https://doi.org/10.1007/0-387-23483-7_461
Publisher Name: Springer, Boston, MA
Print ISBN: 978-0-387-23473-1
Online ISBN: 978-0-387-23483-0
eBook Packages: Computer ScienceReference Module Computer Science and Engineering