## Cryptology ePrint Archive: Report 2010/482

On Instantiation of the Random Oracle

He Ge

Abstract: In the current methodology of the Random Oracle Model, the random oracle is instantiated by a good cryptographic hash function''. However, due to the work of Canetti, Goldreich and Halevi, such methodology has been found problematic because there exist a construction secure in the Random Oracle Model, but any instantiation of the random oracle by any fully specified function which includes also any good cryptographic hash function'' will result in an insecure implementation. We investigate the Canetti-Goldreich-Halevi method, and propose a new method for the instantiation of the random oracle, in which the random oracle is instantiated by a floating pseudorandom function. Under this new method, Canetti, Goldreich and Halevi's construction will have a secure implementation. Our work puts the methodology of the Random Oracle Model on firm grounds.

Category / Keywords: foundations / The Random Oracle Model, Instantiation, Floating Pseudo-Random Function, h-Box

Date: received 10 Sep 2010, withdrawn 5 May 2011

Contact author: sea gehe at gmail com

Available format(s): (-- withdrawn --)

Short URL: ia.cr/2010/482

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