Pointcheval–Stern Signature Algorithm

	Pointcheval–Stern Signature Algorithm In cryptography Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), ..., the Pointcheval–Stern signature algorithm is a digital signature scheme based on the closely related ElGamal signature scheme. It changes the ElGamal scheme slightly to produce an algorithm which has been proven secure in a strong sense against adaptive chosen-message attacks, assuming the discrete logarithm problem is intractable in a strong sense. David Pointcheval and Jacques Stern developed the '' forking lemma'' technique in constructing their proof for this algorithm. It has been used in other security investigations of various cryptographic algorithms. References Digital signature schemes Public-key cryptography {{crypto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Cryptography Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), adversarial behavior. More generally, cryptography is about constructing and analyzing Communication protocol, protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security (confidentiality, data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, Smart card#EMV, chip-based payment cards, digital currencies, password, computer passwords, and military communications. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	ElGamal Signature Scheme The ElGamal signature scheme is a digital signature scheme which is based on the difficulty of computing discrete logarithms. It was described by Taher Elgamal in 1985. (conference version appeared in CRYPTO'84, pp. 10–18) The ElGamal signature algorithm is rarely used in practice. A variant developed at the NSA and known as the Digital Signature Algorithm is much more widely used. There are several other variants. The ElGamal signature scheme must not be confused with ElGamal encryption which was also invented by Taher Elgamal. Overview The ElGamal signature scheme is a digital signature scheme based on the algebraic properties of modular exponentiation, together with the discrete logarithm problem. The algorithm uses a key pair consisting of a public key and a private key. The private key is used to generate a digital signature for a message, and such a signature can be verified by using the signer's corresponding public key. The digital signature provides message authenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Discrete Logarithm Problem In mathematics, for given real numbers a and b, the logarithm \log_b(a) is a number x such that b^x=a. Analogously, in any group G, powers b^k can be defined for all integers k, and the discrete logarithm \log_b(a) is an integer k such that b^k=a. In arithmetic modulo an integer m, the more commonly used term is index: One can write k=\mathbb_b a \pmod (read "the index of a to the base b modulo m") for b^k \equiv a \pmod if b is a primitive root of m and \gcd(a,m)=1. Discrete logarithms are quickly computable in a few special cases. However, no efficient method is known for computing them in general. In cryptography, the computational complexity of the discrete logarithm problem, along with its application, was first proposed in the Diffie–Hellman problem. Several important algorithms in public-key cryptography, such as ElGamal, base their security on the hardness assumption that the discrete logarithm problem (DLP) over carefully chosen groups has no efficient solution. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	David Pointcheval David Pointcheval is a French cryptographer. He is currently the Chief scientific officer (CSO) of Cosmian (on leave from CNRS), a French deeptech company in public cloud security. He is a Senior Researcher at CNRS, and the former head of the Computer Science Department and Cryptography Laboratory at the École normale supérieure. He is mainly known for his contributions in the area of provable security, including the Forking lemma, the Pointcheval-Stern signature algorithm, and his contributions to Password-authenticated key agreement. Biography An alumnus of the École Normale Supérieure, David Pointcheval obtained his Ph.D. in 1996 from the University of Caen Normandy. In 1998, he joined the French National Centre for Scientific Research, working within the Computer Science department of École Normale Supérieure. Since then, his research has focused mostly on asymmetric cryptography and Provable security, of which he was one of the pioneers. He has authored more than 10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Jacques Stern Jacques Stern (born 21 August 1949) is a cryptographer, currently a professor at the École Normale Supérieure. He received the 2006 CNRS Gold medal. His notable work includes the cryptanalysis of numerous encryption and signature schemes, the design of the Pointcheval–Stern signature algorithm, the Naccache–Stern cryptosystem and Naccache–Stern knapsack cryptosystem, and the block ciphers CS-Cipher, DFC, and xmx. He also contributed to the cryptanalysis of the ''SFLASH'' signature scheme. Awards * Knight of the Légion d'honneur recipient * 2005 CNRS Silver Medal * IACR Fellow, 2005 * 2006 CNRS Gold medal * 2007 RSA Award for Excellence in Mathematics Formally called since 2025 The RSAC Conference Award for Excellence in Mathematics, is an annual award. It is announced at the annual RSA Conference in recognition of innovations and contributions in the field of cryptography. An award committee o ... References External links * Public-key cryptographer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Forking Lemma The forking lemma is any of a number of related lemmas in cryptography research. The lemma states that if an adversary (typically a probabilistic Turing machine), on inputs drawn from some distribution, produces an output that has some property with non-negligible probability, then with non-negligible probability, if the adversary is re-run on new inputs but with the same random tape, its second output will also have the property. This concept was first used by David Pointcheval and Jacques Stern in "Security proofs for signature schemes," published in the proceedings of Eurocrypt 1996.Adam Young and Moti Yung, "Malicious Cryptography: Exposing Cryptovirology", Wiley press, 2004, pp. 344. In their paper, the forking lemma is specified in terms of an adversary that attacks a digital signature scheme instantiated in the random oracle model. They show that if an adversary can forge a signature with non-negligible probability, then there is a non-negligible probability that the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Digital Signature Schemes Digital usually refers to something using discrete digits, often binary digits. Businesses Digital bank, a form of financial institution Digital Equipment Corporation (DEC) or Digital, a computer company Digital Research (DR or DRI), a software company Computing and technology Hardware Digital electronics, electronic circuits which operate using digital signals Digital camera, which captures and stores digital images * Digital versus film photography Digital computer, a computer that handles information represented by discrete values Digital recording, information recorded using a digital signal Socioeconomic phenomena * Digital culture, the anthropological dimension of the digital social changes * Digital divide, a form of economic and social inequality in access to or use of information and communication technologies * Digital economy, an economy based on computing and telecommunications resources Digital rights, legal rights of access to computers or the Interne ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]