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Post-quantum Cryptography
In cryptography, post-quantum cryptography (sometimes referred to as quantum-proof, quantum-safe or quantum-resistant) refers to cryptographic algorithms (usually public-key algorithms) that are thought to be secure against a cryptanalytic attack by a quantum computer. The problem with currently popular algorithms is that their security relies on one of three hard mathematical problems: the integer factorization problem, the discrete logarithm problem or the elliptic-curve discrete logarithm problem. All of these problems could be easily solved on a sufficiently powerful quantum computer running Shor's algorithm. Even though current quantum computers lack processing power to break any real cryptographic algorithm, many cryptographers are designing new algorithms to prepare for a time when quantum computing becomes a threat. This work has gained greater attention from academics and industry through the PQCrypto conference series since 2006 and more recently by several workshops ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptography
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing 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 ( data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Learning With Errors
Learning with errors (LWE) is the computational problem of inferring a linear n-ary function f over a finite ring from given samples y_i = f(\mathbf_i) some of which may be erroneous. The LWE problem is conjectured to be hard to solve, and thus to be useful in cryptography. More precisely, the LWE problem is defined as follows. Let \mathbb_q denote the ring of integers modulo q and let \mathbb_q^n denote the set of n- vectors over \mathbb_q . There exists a certain unknown linear function f:\mathbb_q^n \rightarrow \mathbb_q, and the input to the LWE problem is a sample of pairs (\mathbf,y), where \mathbf\in \mathbb_q^n and y \in \mathbb_q, so that with high probability y=f(\mathbf). Furthermore, the deviation from the equality is according to some known noise model. The problem calls for finding the function f, or some close approximation thereof, with high probability. The LWE problem was introduced by Oded Regev in 2005 (who won the 2018 Gödel Prize for this work), it is a ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johannes Buchmann
Johannes Alfred Buchmann (born November 20, 1953, in Cologne) is a German computer scientist, mathematician and professor emeritus at the department of computer science of the Technische Universität Darmstadt. He is known for his research in algorithmic number theory, algebra, post-quantum cryptography and IT security. In 1993, he received the Gottfried Wilhelm Leibniz Prize together with Claus-Peter Schnorr for his work in algorithmic number theory and cryptography. Buchmann also developed the stateful hash-based signature scheme XMSS, the first future-proof secure and practical signature scheme with minimal security requirements, which was declared the first international standard for post-quantum signature schemes in 2018. In addition, he further developed IT security research in Germany. His efforts led to the creation of ATHENE, the largest research center for IT security in Europe. For this he received the Konrad Zuse Medal for Services to Computer Science of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ralph Merkle
Ralph C. Merkle (born February 2, 1952) is a computer scientist and mathematician. He is one of the inventors of public-key cryptography, the inventor of cryptographic hashing, and more recently a researcher and speaker on cryonics. Contributions While an undergraduate, Merkle devised Merkle's Puzzles, a scheme for communication over an insecure channel, as part of a class project. The scheme is now recognized to be an early example of public key cryptography. He co-invented the Merkle–Hellman knapsack cryptosystem, invented cryptographic hashing (now called the Merkle–Damgård construction based on a pair of articles published 10 years later that established the security of the scheme), and invented Merkle trees. The Merkle–Damgård construction is at the heart of many hashing algorithms. While at Xerox PARC, Merkle designed the Khufu and Khafre block ciphers, and the Snefru hash function. Career Merkle was the manager of compiler development at Elxsi from 1980. In 1988, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merkle Signature Scheme
In hash-based cryptography, the Merkle signature scheme is a digital signature scheme based on Merkle trees (also called hash trees) and one-time signatures such as the Lamport signature scheme. It was developed by Ralph Merkle in the late 1970s and is an alternative to traditional digital signatures such as the Digital Signature Algorithm or RSA. NIST has approved specific variants of the Merkle signature scheme in 2020. An advantage of the Merkle signature scheme is that it is believed to be resistant against attacks by quantum computers. The traditional public key algorithms, such as RSA and ElGamal would become insecure if an effective quantum computer could be built (due to Shor's algorithm). The Merkle signature scheme, however, only depends on the existence of secure hash functions. This makes the Merkle signature scheme very adjustable and resistant to quantum computer-based attacks. The Merkle signature is a ''one time signature'' with finite signing potential. The wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamport Signature
In cryptography, a Lamport signature or Lamport one-time signature scheme is a method for constructing a digital signature. Lamport signatures can be built from any cryptographically secure one-way function; usually a cryptographic hash function is used. Although the potential development of quantum computers threatens the security of many common forms of cryptography such as RSA, it is believed that Lamport signatures with large hash functions would still be secure in that event. Each Lamport key can be used to sign a single message. Combined with hash trees, a single key could be used for many messages, making this a fairly efficient digital signature scheme. The Lamport signature cryptosystem was invented in 1979 and named after its inventor, Leslie Lamport. Example Alice has a 256-bit cryptographic hash function and some kind of secure random number generator. She wants to create and use a Lamport key pair, that is, a private key and a corresponding public key. Making the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unbalanced Oil And Vinegar
In cryptography, the unbalanced oil and vinegar (UOV) scheme is a modified version of the oil and vinegar scheme designed by J. Patarin. Both are digital signature protocols. They are forms of multivariate cryptography. The security of this signature scheme is based on an NP-hard mathematical problem. To create and validate signatures, a minimal quadratic equation system must be solved. Solving equations with variables is NP-hard. While the problem is easy if is either much much larger or much much smaller than , importantly for cryptographic purposes, the problem is thought to be difficult in the average case when and are nearly equal, even when using a quantum computer. Multiple signature schemes have been devised based on multivariate equations with the goal of achieving quantum resistance. A significant drawback with UOV is that the key size can be large. Typically , the number of variables, is chosen to be double , the number of equations. Encoding the coefficients of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BLISS Signature Scheme
BLISS (short for Bimodal Lattice Signature Scheme) is a digital signature scheme proposed by Léo Ducas, Alain Durmus, Tancrède Lepoint and Vadim Lyubashevsky in their 2013 paper "Lattice Signature and Bimodal Gaussians". In cryptography, a digital signature ensures that a message is authentically from a specific person who has the private key to create such a signature, and can be verified using the corresponding public key. Current signature schemes rely either on integer factorization, discrete logarithm or elliptic curve discrete logarithm problem, all of which can be effectively attacked by a quantum computer. BLISS on the other hand, is a post-quantum algorithm, and is meant to resist quantum computer attacks. Compared to other post-quantum schemes, BLISS claims to offer better computational efficiency, smaller signature size, and higher security. presentationonce anticipated that BLISS would become a potential candidate for standardization, however it was not submitted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NTRUSign
NTRUSign, also known as the NTRU Signature Algorithm, is an NTRU public-key cryptography digital signature algorithm based on the GGH signature scheme. The original version of NTRUSign was Polynomial Authentication and Signature Scheme (PASS), and was published at CrypTEC'99. The improved version of PASS was named as NTRUSign, and was presented at the rump session of Asiacrypt 2001 and published in peer-reviewed form at the RSA Conference 2003. The 2003 publication included parameter recommendations for 80-bit security. A subsequent 2005 publication revised the parameter recommendations for 80-bit security, presented parameters that gave claimed security levels of 112, 128, 160, 192 and 256 bits, and described an algorithm to derive parameter sets at any desired security level. NTRU Cryptosystems, Inc. have applied for a patent on the algorithm. NTRUSign involves mapping a message to a random point in 2''N''-dimensional space, where ''N'' is one of the NTRUSign parameters, and solv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GGH Encryption Scheme
The Goldreich–Goldwasser–Halevi (GGH) lattice-based cryptosystem is an asymmetric cryptosystem based on lattices. There is also a GGH signature scheme. The Goldreich–Goldwasser–Halevi (GGH) cryptosystem makes use of the fact that the closest vector problem can be a hard problem. This system was published in 1997 by Oded Goldreich, Shafi Goldwasser, and Shai Halevi, and uses a trapdoor one-way function which relies on the difficulty of lattice reduction. The idea included in this trapdoor function is that, given any basis for a lattice, it is easy to generate a vector which is close to a lattice point, for example taking a lattice point and adding a small error vector. But to return from this erroneous vector to the original lattice point a special basis is needed. The GGH encryption scheme was cryptanalyzed (broken) in 1999 by . Nguyen and Oded Regev had cryptanalyzed the related GGH signature scheme in 2006. Operation GGH involves a ''private key'' and a '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NTRU
NTRU is an open-source public-key cryptosystem that uses lattice-based cryptography to encrypt and decrypt data. It consists of two algorithms: NTRUEncrypt, which is used for encryption, and NTRUSign, which is used for digital signatures. Unlike other popular public-key cryptosystems, it is resistant to attacks using Shor's algorithm. NTRUEncrypt was patented, but it was placed in the public domain in 2017. NTRUSign is patented, but it can be used by software under the GPL. History The first version of the system, which was called NTRU, was developed in 1996 by mathematicians Jeffrey Hoffstein, Jill Pipher, and Joseph H. Silverman. That same year, the developers of NTRU joined with Daniel Lieman and founded the company NTRU Cryptosystems, Inc., and were given a patent on the cryptosystem. The name "NTRU", chosen for the company and soon applied to the system as well, was originally derived from the pun ''Number Theorists 'R' Us'' or, alternatively, stood for ''Number Theory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring Learning With Errors Signature
Digital signatures are a means to protect digital information from intentional modification and to authenticate the source of digital information. Public key cryptography provides a rich set of different cryptographic algorithms the create digital signatures. However, the primary public key signatures currently in use ( RSA and Elliptic Curve Signatures) will become completely insecure if scientists are ever able to build a moderately sized quantum computer. Post quantum cryptography is a class of cryptographic algorithms designed to be resistant to attack by a quantum cryptography. Several post quantum digital signature algorithms based on hard problems in lattices are being created replace the commonly used RSA and elliptic curve signatures. A subset of these lattice based scheme are based on a problem known as Ring learning with errors. Ring learning with errors based digital signatures are among the post quantum signatures with the smallest public key and signature sizes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
