Cryptology ePrint Archive: Report 2004/164
ID-based Cryptography from Composite Degree Residuosity
Man Ho Au and Victor K. Wei
Abstract: We present identity-based identification (resp. encryption, signature, blind signature,ring signature) from composite degree residuosity (CDR). Constructions of identifications and signatures
motivated by several existing CDR-based bandwidth-efficient
encryption schemes are presented. Their securities are proven equivalent to famous hard problems, in the random oracle model.
Motivated by Cocks,we construct an identity-based encryption from CDR. Its security is proven equivalent to a new problem, the JSR (Jacobi Symbol of Roots of two quadratic polynomials) Problem. We prove JSR is at least as hard as QRP (Quadratic Residuosity Problem). Furthermore, we present the first two-way equivalence reduction of the security of Cocks' IBE, to the JSR Problem.
Category / Keywords: ID-based Cryptography
Date: received 12 Jul 2004, last revised 12 Jul 2004
Contact author: mhau3 at ie cuhk edu hk
Available format(s): PDF | BibTeX Citation
Version: 20040714:190534 (All versions of this report)
Short URL: ia.cr/2004/164
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