Eecient Convertible Undeniable Signature Schemes
نویسندگان
چکیده
Undeniable signatures are digital signatures which are not universally veriiable but can only be checked with the signer's help. However, the signer cannot deny the validity of a correct signature. An extended concept , convertible undeniable signatures, allows the signer to convert single undeniable signatures or even the whole scheme into universally veriiable signatures or into an ordinary digital signature scheme, respectively. In this paper we propose a new convertible undeniable signature scheme and provide proofs for all relevant security properties. The scheme is based on Schnorr's signature scheme and it is eecient. Unlike previous eecient solutions, this new scheme can be used as a basis for an eecient extension to threshold signatures, where the capability of signing (and of verifying signatures) is shared among n parties using a t out of n threshold scheme.
منابع مشابه
Eecient Convertible Undeniable Signature Schemes Extended Abstract
Undeniable signatures are digital signatures which are not universally veri able but can only be checked with the signer's help. However, the signer cannot deny the validity of a correct signature. An extended concept, convertible undeniable signatures, allows the signer to convert single undeniable signatures or even the whole scheme into universally veri able signatures or into an ordinary di...
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