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Sci.crypt
There are several newsgroups relevant for discussions about cryptography and related issues. *sci.crypt — an unmoderated forum for discussions on technical aspects of cryptography. * sci.crypt.research — a similar, moderated group, focusing on research into cryptography. It was founded based on a charter by Peter Gutmann. *sci.crypt.random-numbers — discuss generation of cryptographically secure random numbers. *talk.politics.crypto — discussions of the relationship between cryptography and government. The original charter was by D.J. Silverton. *alt.security.pgp — discussion of Pretty Good Privacy (PGP) and related software. sci.crypt In 1995, Bruce Schneier commented, "It is read by an estimated 100,000 people worldwide. Most of the posts are nonsense, bickering, or both; some are political, and most of the rest are requests for information or basic questions. Occasionally nuggets of new and useful information are posted to this newsgroup." Appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Khufu And Khafre
In cryptography, Khufu and Khafre are two block ciphers designed by Ralph Merkle in 1989 while working at Xerox's Palo Alto Research Center. Along with Snefru, a cryptographic hash function, the ciphers were named after the Egyptian Pharaohs Khufu, Khafre and Sneferu. Under a voluntary scheme, Xerox submitted Khufu and Khafre to the US National Security Agency (NSA) prior to publication. NSA requested that Xerox not publish the algorithms, citing concerns about national security. Xerox, a large contractor to the US government, complied. However, a reviewer of the paper passed a copy to John Gilmore, who made it available via the sci.crypt newsgroup. It would appear this was against Merkle's wishes. The scheme was subsequently published at the 1990 CRYPTO conference (Merkle, 1990). Khufu and Khafre were patented by Xerox; the patent was issued on March 26, 1991. Khufu Khufu is a 64-bit block cipher which, unusually, uses keys of size 512 bits; block ciphers typically have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RC4 (cipher)
In cryptography, RC4 (Rivest Cipher 4, also known as ARC4 or ARCFOUR, meaning Alleged RC4, see below) is a stream cipher. While it is remarkable for its simplicity and speed in software, multiple vulnerabilities have been discovered in RC4, rendering it insecure. It is especially vulnerable when the beginning of the output keystream is not discarded, or when nonrandom or related keys are used. Particularly problematic uses of RC4 have led to very insecure protocols such as WEP. , there is speculation that some state cryptologic agencies may possess the capability to break RC4 when used in the TLS protocol. IETF has published RFC 7465 to prohibit the use of RC4 in TLS; Mozilla and Microsoft have issued similar recommendations. A number of attempts have been made to strengthen RC4, notably Spritz, RC4A, VMPC, and RC4+. History RC4 was designed by Ron Rivest of RSA Security in 1987. While it is officially termed "Rivest Cipher 4", the RC acronym is alternatively understood to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-1 Block Cipher
In cryptography, the S-1 block cipher was a block cipher posted in source code form on Usenet on 11 August 1995. Although incorrect security markings immediately indicated a hoax, there were several features of the code which suggested it might be leaked source code for the Skipjack cipher, which was still classified at the time. However once David Wagner had discovered a severe design flaw, involving the key schedule but not the underlying round function, it was generally accepted as being a hoax—but one with an astonishing amount of work behind it. Bruce Schneier Bruce Schneier (; born January 15, 1963) is an American cryptographer, computer security professional, privacy specialist, and writer. Schneier is an Adjunct Lecturer in Public Policy at the Harvard Kennedy School and a Fellow at the Berkman ... noted that S-1 contained a feature never seen before in the open literature; a G-table that results in key and data dependent rotation of S-boxes to use in a given r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubber-hose Cryptanalysis
In cryptography and steganography, plausibly deniable encryption describes encryption techniques where the existence of an encrypted file or message is deniable in the sense that an adversary cannot prove that the plaintext data exists. The users may convincingly deny that a given piece of data is encrypted, or that they are able to decrypt a given piece of encrypted data, or that some specific encrypted data exists. Such denials may or may not be genuine. For example, it may be impossible to prove that the data is encrypted without the cooperation of the users. If the data is encrypted, the users genuinely may not be able to decrypt it. Deniable encryption serves to undermine an attacker's confidence either that data is encrypted, or that the person in possession of it can decrypt it and provide the associated plaintext. In their pivotal 1996 paper, Ran Canetti, Cynthia Dwork, Moni Naor, and Rafail Ostrovsky introduced the concept of deniable encryption, a cryptographic breakthr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iraqi Block Cipher
In cryptography, the Iraqi block cipher was a block cipher published in C source code form by anonymous FTP upload around July 1999, and widely distributed on Usenet. It is a five round unbalanced Feistel cipher operating on a 256 bit block with a 160 bit key. The source code shows that the algorithm operates on blocks of 32 bytes (or 256 bits). That's four times larger than DES or 3DES (8 bytes) and twice as big as Twofish or AES (16 bytes). It also shows that the key size can vary from 160 to 2048 bits. A detailed analysis of the source code of the algorithm shows that it uses a 256-byte S-Box that is key-dependant (as on Blowfish, it uses a first fixed S table that will generate, with the key, the second S-Box used for encryption/decryption). The algorithm also uses a 16-column x 16-row P-Box, which is also key-dependent and also initialized from a fixed P table. Each round uses one row from P-Box and 16 columns, which means that the algorithm can use up to 16 rounds. A com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newsgroup
A Usenet newsgroup is a repository usually within the Usenet system for messages posted from users in different locations using the Internet. They are not only discussion groups or conversations, but also a repository to publish articles, start developing tasks like creating Linux, sustain mailing lists and file uploading. That’s thank to the protocol that poses no article size limit, but are to the providers to decide. In the late 1980s, Usenet articles were often limited by the providers to 60,000 characters, but in time, Usenet groups have been split into two types: ''text'' for mainly discussions, conversations, articles, limited by most providers to about 32,000 characters, and ''binary'' for file transfer, with providers setting limits ranging from less than 1 MB to about 4 MB. Newsgroups are technically distinct from, but functionally similar to, discussion forums on the World Wide Web. Newsreader software is used to read the content of newsgroups. Before the adoption ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Usenet Newsgroup
A Usenet newsgroup is a repository usually within the Usenet system for messages posted from users in different locations using the Internet. They are not only discussion groups or conversations, but also a repository to publish articles, start developing tasks like creating Linux, sustain mailing lists and file uploading. That’s thank to the protocol that poses no article size limit, but are to the providers to decide. In the late 1980s, Usenet articles were often limited by the providers to 60,000 characters, but in time, Usenet groups have been split into two types: ''text'' for mainly discussions, conversations, articles, limited by most providers to about 32,000 characters, and ''binary'' for file transfer, with providers setting limits ranging from less than 1 MB to about 4 MB. Newsgroups are technically distinct from, but functionally similar to, discussion forums on the World Wide Web. Newsreader software is used to read the content of newsgroups. Before the adoption ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter Gutmann (computer Scientist)
Peter Claus Gutmann is a computer scientist in the Department of Computer Science at the University of Auckland, Auckland, New Zealand. He has a Ph.D. in computer science from the University of Auckland. His Ph.D. thesis and a book based on the thesis were about a cryptographic security architecture. He is interested in computer security issues, including security architecture, security usability (or more usually the lack thereof), and hardware security; he has discovered several flaws in publicly released cryptosystems and protocols. He is the developer of the cryptlib open source software security library and contributed to PGP version 2. In 1994 he developed the Secure FileSystem (SFS). He is also known for his analysis of data deletion on electronic memory media, magnetic and otherwise, and devised the Gutmann method for erasing data from a hard drive more or less securely. These analyses have gained great popularity, although they are based on numerous inaccuracies an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptographically Secure Pseudorandom Number Generator
A cryptographically secure pseudorandom number generator (CSPRNG) or cryptographic pseudorandom number generator (CPRNG) is a pseudorandom number generator (PRNG) with properties that make it suitable for use in cryptography. It is also referred to as a cryptographic random number generator (CRNG). Background Most cryptographic applications require random numbers, for example: * key generation * initialization vectors * nonces * salts in certain signature schemes, including ECDSA and RSASSA-PSS * token generation The "quality" of the randomness required for these applications varies. For example, creating a nonce in some protocols needs only uniqueness. On the other hand, the generation of a master key requires a higher quality, such as more entropy. And in the case of one-time pads, the information-theoretic guarantee of perfect secrecy only holds if the key material comes from a true random source with high entropy, and thus just any kind of pseudorandom number gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pretty Good Privacy
Pretty Good Privacy (PGP) is an encryption software, encryption program that provides cryptographic privacy and authentication for data communication. PGP is used for digital signature, signing, encrypting, and decrypting texts, Email, e-mails, files, directories, and whole disk partitions and to increase the security of e-mail communications. Phil Zimmermann developed PGP in 1991. PGP and similar software follow the OpenPGP standard (RFC 4880), an open standard for encryption, encrypting and decrypting data. Modern versions of PGP are interoperability, interoperable with GnuPG and other OpenPGP-compliant systems. The OpenPGP standard has received criticism for its long-lived keys and the difficulty in learning it, as well as the EFAIL, Efail security vulnerability that previously arose when select e-mail programs used OpenPGP with S/MIME. The new OpenPGP standard (RFC 9580) has also been criticised by the maintainer of GnuPG Werner Koch, who in response created his own speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bruce Schneier
Bruce Schneier (; born January 15, 1963) is an American cryptographer, computer security professional, privacy specialist, and writer. Schneier is an Adjunct Lecturer in Public Policy at the Harvard Kennedy School and a Fellow at the Berkman Klein Center for Internet & Society as of November, 2013. He is a board member of the Electronic Frontier Foundation, Access Now, and The Tor Project; and an advisory board member of Electronic Privacy Information Center and VerifiedVoting.org. He is the author of several books on general security topics, computer security and cryptography and is a squid enthusiast. Early life and education Bruce Schneier is the son of Martin Schneier, a Brooklyn Supreme Court judge. He grew up in the Flatbush neighborhood of Brooklyn, New York, attending P.S. 139 and Hunter College High School. After receiving a physics bachelor's degree from the University of Rochester in 1984, he went to American University in Washington, D.C., and got his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
