A secure instantiation of the random oracle by a computable function
نویسندگان
چکیده
In this paper we investigate the problem of secure instantiation of the random oracle, based on the concepts and methods of algorithmic randomness. We show that, for any secure signature scheme in the random oracle model, there exists a specific computable function which can instantiate the random oracle while keeping the security originally proved in the random oracle model. Our results use the general form of definitions of security notions for signature schemes, and depend neither on specific schemes nor on specific security notions. Keywords— cryptography, random oracle model, provable security, cryptographic hash function, algorithmic random-
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