saved book title Cryptography subtitle cover image Jules verne cryptogramme.png cover color rgb 255,255,255 Cryptography Overview Cryptography Cryptanalysis History of cryptography Classical cryptography Caesar cipher Substitution cipher Transposition cipher Vigen re cipher One time pad Modern cryptography Symmetric key algorithm Public key cryptography Cryptographic hash function Major symmetric key algorithms Stream cipher Block cipher RC4 Data Encryption Standard Advanced Encryption Standard Feistel cipher Major public key systems RSA algorithm RSA Diffie Hellman key exchange Elliptic curve cryptography NSA Suite B Cryptography Cryptographic hash functions MD5 SHA 1 SHA 2 NIST hash function competition SHA 3 Message authentication code Key management Key cryptography Cryptographic key Key management Key size Public key infrastructure Web of trust Cryptanalysis Frequency analysis Cryptanalysis of the Enigma Man in the middle attack Differential cryptanalysis Side channel attack Random number generator attack Rainbow table Applications of cryptography Transport Layer Security Pretty Good Privacy GNU Privacy Guard Digital signature Digital rights management Cipher machines Jefferson disk Enigma machine Purple cipher machine The Purple cryptographic machine SIGABA KL 7 Fialka NSA encryption systems Voice encryption SIGSALY STU III Secure Terminal Equipment Secure Communications Interoperability Protocol Category Cryptography books ... more details
unreferenced date April 2010 ambox type move text A majority of the content was moved to Export of cryptography in the United States on 19 January 2010 The export of cryptography is the transfer from one country to another of devices and technology related to cryptography . Note Copied from Expor of cryptography in the United States In the early days of the Cold War , the U.S. and its allies developed an elaborate series of export control regulations designed to prevent a wide range of Western technology from falling into the hands of others, particularly the Eastern bloc . All export of technology classed as critical required a license. CoCom was organized to coordinate Western export controls. Currently, many countries, notably those participating in the Wassenaar Arrangement , have similar restrictions. Citation needed date March 2009 See also Export of cryptography in the United States Restrictions on the import of cryptography crypto stub DEFAULTSORT Export Of Cryptography Category Cryptography law Category Computer law Category Export and import control it Esportazione della crittografia ... more details
Financial cryptography FC is the use of cryptography in applications in which financial loss could result from subversion of the message system. Cryptographers think of the field as originating in the work of Dr David Chaum who invented the blind signature blinded signature . This special form of a digital signature cryptographic signature permitted a virtual coin to be signed without the signer seeing the actual coin, and permitted a form of digital token money that offered untraceability. This form is sometimes known as Digital Cash . A widely used and previously developed cryptographic mechanism ... transfers. However, it was the work of David Chaum that excited the cryptography community about the potential of encrypted messages as actual financial instruments . Financial cryptography includes ... of Financial Cryptography. Hashcash is being used to limit spam. Financial cryptography is distinguished from traditional cryptography in that for most of recorded history, cryptography has been used ... of cryptography and only the simplest ideas were adopted. Account money systems protected by Secure ... mechanisms, including blinded token money, were not. Financial cryptography is frequently seen to have a very broad scope of application. Ian Grigg sees financial cryptography in seven layers http iang.org papers fc7.html , being the combination of seven distinct disciplines cryptography, software ... so, given that finance and cryptography are each built upon multiple disciplines. Financial cryptography is to some extent organized around the annual meeting of the International Financial Cryptography Association http www.ifca.ai Financial Cryptography , which is held each year in a different location ... key exchange External links http www.ifca.ai International Financial Cryptography Association http fincrypt.blogspot.com Fincrypt weblog https www.financialcryptography.com Financial Cryptography weblog ... Financial cryptography Category Banking technology ca Criptografia financera es Criptograf a financiera ... more details
In the cryptography sense, a keyring stores known encryption keys and in some cases, passwords . For example, GNU Privacy Guard makes use of keyrings. ref http www.gnupg.org gph en manual.html GPG Privacy Handbook ref References Reflist crypto stub Category Cryptography ... more details
There are several newsgroup s relevant for discussions about cryptography and related issues. news sci.crypt sci.crypt &mdash an unmoderated forum for discussions on technical aspects of cryptography . news sci.crypt.research sci.crypt.research &mdash a similar, Usenet newsgroup Moderated newsgroups moderated group, focusing on research into cryptography. It was founded based on a charter by Peter Gutmann computer scientist Peter Gutmann . news sci.crypt.random numbers sci.crypt.random numbers &mdash discuss Cryptographically secure pseudorandom number generator generation of cryptographically secure random number s. news talk.politics.crypto talk.politics.crypto &mdash discussions of the relationship between cryptography and government. The original charter was by D.J. Silverton. news alt.security.pgp alt.security.pgp &mdash 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. Practical Cryptography Less mathematical Applied Cryptography , 2nd ed, pages 608 609 . Leaked descriptions of secret algorithms have been posted to the Internet via sci.crypt, for example RC2 , RC4 cipher RC4 and Khufu and Khafre . Others have been hoaxes Iraqi block cipher and S 1 block cipher S 1 , the latter an alleged description of the then secret Skipjack cipher Skipjack cipher. The group is also the origin of the term, Rubber hose cryptanalysis . External links http www.alt security keydist.info newsgroups Newsgroups for cryptography http www.faqs.org faqs cryptography faq sci.crypt Frequently Asked Questions crypto stub Category Cryptography journals Category Sci. hierarchy fr Groupes de discussion sur la cryptologie ... more details
Refimprove date December 2009 Orphan date December 2009 Cryptography is the practice and study of hiding information . There are many different cryptography laws in different nations . Some countries prohibit export of cryptography software and or encryption algorithm s or cryptoanalysis methods. In some countries a license is required to use encryption software, and a few countries ban citizens from encrypting their internet communication. Some countries require decryption keys to be recoverable in case of a police investigation. France As of 2011 and since 2004, the law for trust in the digital economy LCEN ref cite web accessdate June 14, 2011 url http www.legifrance.gouv.fr affichTexte.do?cidTexte JORFTEXT000000801164 title Legifrance.gouv.fr Loi pour la confiance dans l conomie num rique LCEN ref mostly liberalized the use of cryptography. Especially As long as cryptography is only used for authentication and integrity purposes, it can be freely used. The cryptographic key or the nationality of the entities involved in the transaction do not matter. Typical e business websites fall under this liberalized regime. For other uses, exportation and importation to or from foreign countries must be either declared when the other country if a member of the European Union or requires an explicit authorization for other countries . See also Official Secrets Act United Kingdom , India , Ireland , Malaysia and formerly New Zealand Regulation of Investigatory Powers Act 2000 United Kingdom Restrictions on the Import of Cryptography Export of cryptography Key disclosure law United States v. Boucher on right of criminal defendant not to reveal passphrase References Reflist DEFAULTSORT Cryptography Laws In Different Nations Category Cryptography law Law stub ... more details
dablink MAG is also IATA code for Madang Airport Refimprove date August 2008 In cryptography , MAG is stream cipher algorithm developed by Rade Vuckovac . It has been submitted to the eSTREAM Project of the eCRYPT network. It has not been selected for focus, nor for consideration in Phase 2 it has been archived . Cryptography navbox stream Category Stream ciphers crypto stub nl MAG ... more details
In cryptography , GMR is a digital signature algorithm named after its inventors Shafi Goldwasser , Silvio Micali and Ron Rivest . As with RSA algorithm RSA the security of the system is related to the difficulty of Integer factorization factoring very large numbers . But, in contrast to RSA, GMR is secure against adaptive chosen plaintext attack chosen message attack s &mdash even when an attacker receives signatures for messages of his choice, this does not allow him to forge a signature for a single additional message. External links http citeseer.ist.psu.edu goldwasser88digital.html A Digital Signature Scheme Secure Against Adaptive Chosen Message Attacks Shafi Goldwasser, Silvio Micali, Ronald L. Rivest Cryptography navbox public key Category Digital signature schemes Category Lattice based cryptography crypto stub de GMR Signaturverfahren ... more details
Infobox Company company name Cryptography Research, Inc. company logo File Cryptography Research logo.png 142px Cryptography Research, Inc. Logo type Private company Private subsidiary founded 1995 location San Francisco , California key people Paul Kocher , President and Chief Scientist products Technology licensing, secure semiconductors revenue 10M 100M num employees 25 100 homepage http www.cryptography.com www.cryptography.com parent Rambus Cryptography Research, Inc.. is a San Francisco based cryptography company specializing in applied cryptographic engineering, including technologies for building tamper resistant semiconductors. It was purchased on June 6, 2011 by Rambus for more than 250M in cash and stock. ref cite web url http www.rambus.com us news press releases 2011 110606.html title Rambus completes acquisition of Cryptography Research date 2011 06 06 accessdate 2011 06 29 ref The company licenses patents for protecting cryptographic devices against power analysis attacks. ref http www.frost.com prod servlet market insight top.pag?docid 28127384 Ubhey, Anoop, Interview with Cryptography Research Inc , Frost & Sullivan, 23 Nov. 2004. ref The company s CryptoFirewall brand ASIC cores are used in pay TV conditional access systems and anti counterfeiting applications. ref http www.devicelink.com mddi archive 07 10 020.html Maria Fontanezza, Technology Battles Device Cloning , MD&DI, October 2007. ref CRI also developed BD , a security component in the Blu ray disc format, and played a role in the format war between HD DVD and Blu ray . ref http query.nytimes.com gst fullpage.html?res 9B07E7D9103BF936A25757C0A9659C8B63 Markoff, John, Plan Would Use Content, Not Devices .... ref The company s services group assists with security testing, disaster recovery, and training. Cryptography ... prod servlet press release.pag?docid 179970706 Frost & Sullivan Commends Cryptography Research ... Cryptography Research website Category Cryptography companies crypto stub ru Cryptography ... more details
about the United States government cryptography project other uses Capstone disambiguation Capstone is the name of a United States government long term project to develop cryptography standards for public and government use. Capstone was driven by the National Institute of Standards and Technology NIST and the National Security Agency NSA the project began in 1993 ref Note1 . The initiative involved four standard algorithms a data encrypt encryption algorithm called Skipjack cipher Skipjack , along with the Clipper chip that included the Skipjack algorithm, a digital signature algorithm, Digital Signature Algorithm DSA , a hash function, SHA 1 , and a key exchange protocol. ref Note2 Captstone s first implementation was in the Fortezza PCMCIA card . The initiative encountered massive resistance from the cryptographic community, and eventually the US government abandoned the effort. The main reasons for this resistance were concerns about Skipjack cipher Skipjack s design, which was Classified information classified , and the use of key escrow in the Clipper chip. See also Clipper chip Skipjack cipher Skipjack Fortezza References note Note1 http www.eff.org Privacy Key escrow Clipper wh crypto original.announce Original press release note Note2 http www.rsasecurity.com rsalabs node.asp?id 2317 RSA Laboratories FAQ on Cryptography entry note Note3 http www.eff.org Privacy Key escrow Clipper EFF archives on Capstone crypto stub Category National Security Agency encryption devices Category History of cryptography ... more details
on cryptology . Books on cryptography have been published sporadically and with highly variable ... in cryptography and secure information transfer communications of the last 25 years when reason WP ... of a book about cryptography was a Roman work, now lost and known only by references. Many early cryptographic works were esoteric, mystical, and or reputation promoting cryptography being mysterious .... Friedman William Friedman in the early 20th century also wrote books on cryptography. These authors ... to protect communications. By the end of World War I , cryptography and its literature began to be officially ... century most aspects of modern cryptography were regarded as the special concern of governments ... work to be published on cryptography in this period is undoubtedly David Kahn writer David Kahn s The Codebreakers ... practice of cryptography was available. Kahn has said that over ninety percent of its content was previously .... List Merge to List of important publications in cryptography date October 2011 Significant books on cryptography include Helen Fouch Gaines Gaines, Helen Fouch Cryptanalysis , 1939, Dover, ISBN ... as one of the first projects of the American Cryptogram Association . Dominic Welsh Codes and Cryptography ... , Rowman & Littlefield, ISBN 0 8476 7438 X Konheim, Alan G. 1981 . Cryptography A Primer , John ... and Yehuda Lindell s Introduction to Modern Cryptography , ref http www.cs.umd.edu jkatz imc.html ref CRC Press. Presents modern cryptography at a level appropriate for undergraduates, graduate students ... science background. Mao, Wenbo 2004 . Modern Cryptography Theory and Practice ISBN 0 13 066943 1. An up to date book on cryptography. Touches on provable security, and written with students and practitioners in mind. Douglas Stinson Cryptography Theory and Practice ISBN 1 58488 508 4. Covers ... Nigel Smart Cryptography An introduction ISBN 0 07 709987 7 http www.cs.bris.ac.uk nigel Crypto Book online version . Similar in intent to Applied Cryptography but less comprehensive. Covers more ... more details
PMAC , which stands for Parallelizable MAC , is a message authentication code algorithm. It was created by Phillip Rogaway patent pending . PMAC is a method of taking a block cipher and creating an efficient message authentication code that is provably reducible in security to the underlying block cipher. PMAC is similar in functionality to the OMAC cryptography OMAC algorithm. External links http www.cs.ucdavis.edu rogaway ocb pmac.htm Phil Rogaway s page on PMAC Changhoon Lee, Jongsung Kim, Jaechul Sung, Seokhie Hong, Sangjin Lee. Forgery and Key Recovery Attacks on PMAC and Mitchell s TMAC Variant , 2006. http www.cosic.esat.kuleuven.be publications article 779.ps ps Cryptography navbox hash Category Message authentication codes crypto stub ... more details
Certificateless cryptography is a variant of ID based cryptography intended to prevent the key escrow problem. Ordinarily, keys are generated by a certificate authority or a key generation center KGC who is given complete power and is implicitly trusted. To prevent a complete breakdown of the system in the case of a compromised KGC, the key generation process is split between the KGC and the user. The KGC first generates a key pair, where the private key is now the partial private key of the system. The remainder of the key is a random value generated by the user, and is never revealed to anyone, not even the KGC. All cryptographic operations by the user are performed by using a complete private key which involves both the KGC s partial key, and the user s random secret value. One disadvantage of this is that the identity information no longer forms the entire public key. To encrypt a message to another user, three pieces of information are needed 1 the other user s public key and 2 identity, and also 3 the third party s public information. To decrypt, a user just needs to use their private key. For tight security, a certificateless system has to prove its security against two types of adversaries. Type 1 Adversary Refers to any third party who can fake the user s public keys, corresponding to the user s random secret value. Type 2 Adversary Refers to a compromised or malicious KGC, who has access to the partial public and private keys of all users. References Sattam S. Al Riyami and Kenneth G. Paterson, Certificateless Public Key Cryptography, Lecture Notes in Computer Science , pp. 452 473, 2003 http eprint.iacr.org 2003 126.pdf . Category Public key cryptography Category Identity based cryptography es Criptograf a sin certificados ... more details
Visual cryptography is a cryptography cryptographic technique which allows visual information pictures, text, etc. to be encrypted in such a way that decryption becomes a mechanical operation that does not require a computer. One of the best known techniques has been credited to Moni Naor and Adi Shamir , who developed it in 1994. They demonstrated a visual secret sharing scheme, where an image was broken up into n shares so that only someone with all n shares could decrypt the image, while any n 1 shares revealed no information about the original image. Each share was printed on a separate transparency, and decryption was performed by overlaying the shares. When all n shares were overlaid, the original image would appear. Using a similar idea, transparencies can be used to implement a one time pad encryption, where one transparency is a shared random pad, and another transparency acts as the ciphertext. Example Image Visual crypto animation demo.gif frame right A demonstration of visual cryptography In this example, the Wikipedia logo has been split into two shares. Each white pixel ... shares reveal no information about the original image. 2, N Visual Cryptography Sharing Case Sharing ... parties to cheat an honest party in visual cryptography. They take advantage of knowing the underlying ... other honest parties. References Moni Naor and Adi Shamir, Visual Cryptography, EUROCRYPT 1994, pp1 ... visual cryptography Open source Matlab implementation of Visual Cryptography in Algorito http users.telenet.be d.rijmenants en visualcrypto.htm Visual Cryptography on Cipher Machines & Cryptology http www.cacr.math.uwaterloo.ca dstinson visual.html Doug Stinson s visual cryptography page http www fs.informatik.uni ... create and encode images Horng, G, Tzungher C. and Tasi, D.S. Cheating in Visual Cryptography, Designs, Codes and Cryptography, 2006, pp219&ndash 236 http www.springerlink.com content f468p22hw6382256 ... Category Cryptography crypto stub de Visuelle Kryptographie it Crittografia visuale he ... more details
see also Index of cryptography articles The following outline is provided as an overview of and topical guide to cryptographyCryptography or cryptology &ndash practice and study of hiding information . Modern cryptography intersects the disciplines of mathematics , computer science , and engineering . Applications of cryptography include automated teller machine ATM cards , password computer passwords , and electronic commerce . Essence of cryptography Main article Cryptography Cryptographer &ndash ... &ndash Branches of cryptography Cryptographic engineering &ndash Multivariate cryptography &ndash Quantum cryptography &ndash Steganography &ndash Visual cryptography &ndash History of cryptography main History of cryptography Timeline of cryptography Japanese cryptology from the 1500s to Meiji &ndash World War I cryptography &ndash World War II cryptography &ndash Reservehandverfahren &ndash Venona ... &ndash Grille cryptography Grille &ndash Permutation cipher Permutation &ndash VIC cipher VIC ... Chameleon cipher Chameleon &ndash FISH cipher FISH &ndash by Siemens AG Fish cryptography WWII Fish ... cryptography STURGEON by Bletchley Park Pike cipher Pike &ndash improvement on FISH by Ross J. Anderson ... recommendation El Gamal &ndash discrete logarithm Elliptic curve cryptography &ndash discrete logarithm ... main Key cryptography Authentication main Key authentication Public key infrastructure &ndash X.509 ... ID based cryptography &ndash Certificate based encryption &ndash Secure key issuing cryptography &ndash Certificateless cryptography &ndash Hash tree Merkle tree &ndash Transport exchange Diffie Hellman ... cryptography Salt &ndash Cryptographic hash functions main Cryptographic hash function Message authentication ... &ndash by Ross J. Anderson Ross Anderson et al. Snefru cryptography Snefru &ndash Whirlpool algorithm ... cryptography Malleability &ndash Uncracked codes and ciphers maincat Uncracked codes and ciphers ... projects Standards main Cryptography standards Federal Information Processing Standard s Publication ... more details
Use dmy dates date August 2010 More footnotes date July 2009 The history of cryptography began thousands of years ago. Until recent decades, it has been the story of what might be called classical cryptography classic cryptography that is, of methods of encryption that use pen and paper, or perhaps simple .... The development of cryptography has been paralleled by the development of cryptanalysis the breaking ... cryptography was largely the preserve of governments. Two events have since brought it squarely into the public ... of public key cryptography . Classical cryptography See also Classical cipher The earliest known use of cryptography is found in non standard Egyptian hieroglyphs hieroglyphs carved into monuments ... history.htm A Brief History of Cryptography. CYCOM Cypher Research Laboratories.24 Jan. 2006 ref ... These are examples of still other uses of cryptography, or of something that looks impressively if misleadingly ... http cryptozine.blogspot.com 2008 05 brief history of cryptography.html A Brief History of Cryptography .... A Short History of Cryptography. 1995. ref Image Skytala&EmptyStrip Shaded.png thumb 199px right ... examples of cryptography per se as the message, once known, is directly readable ... Cryptography Polybius Square . ref name Cohen The Ancient Rome Romans knew something of cryptography e.g., the Caesar cipher and its variations . Medieval cryptography File Al kindi cryptographic.gif ... . It was the most fundamental cryptanalytic advance until WWII. Al Kindi wrote a book on cryptography ... lived from 1312 to 1361, but whose writings on cryptography have been lost. The list of ciphers in this work ... cypher http www.cypher.com.au crypto history.htm History of Cryptography ref In Europe, cryptography ... may be inherent in cryptography for it was then, and remains today, fundamentally difficult ..., as may be expected, are common. Cryptography, cryptanalysis , and secret agent courier betrayal ... the end of the Muslim Golden Age at the hand of the Mongols, cryptography remained comparatively ... more details
There are a number of standardization standards related to cryptography . Standard algorithms and protocols provide a focus for study standards for popular applications attract a large amount of cryptanalysis . Encryption standards Data Encryption Standard DES, now obsolete Triple DES Advanced Encryption Standard AES RSA algorithm RSA the original public key algorithm OpenPGP CipherSaber Hash standards MD5 128 bit obsolescent SHA 1 160 bit SHA 2 available in 224, 256, 384 and 512 bit variants HMAC keyed hash PBKDF2 Key derivation function RFC 2898 Digital signature standards Digital Signature Standard DSS , based on the Digital Signature Algorithm DSA RSA algorithm RSA Public key infrastructure PKI standards X.509 Public Key Certificates Wireless Standards Wired Equivalent Privacy WEP , severely flawed and superseded by WPA Wi Fi Protected Access WPA better than WEP, a pre standard partial version of 802.11i 802.11i a.k.a. WPA2, uses Advanced Encryption Standard AES and other improvements on WEP A5 1 and A5 2 cell phone encryption for GSM U.S. Government Federal Information Processing Standards FIPS FIPS PUB 31 Guidelines for Automatic Data Processing Physical Security and Risk Management 1974 FIPS PUB 46 3 Data Encryption Standard Data Encryption Standard DES 1999 FIPS PUB 73 Guidelines for Security of Computer Applications 1980 FIPS PUB 74 Guidelines for Implementing and Using the NBS Data Encryption Standard 1981 FIPS PUB 81 Data Encryption Standard DES Modes of Operation 1980 FIPS PUB 102 Guideline for Computer Security Certification and Accreditation 1983 FIPS PUB 112 Password ... of local area network Security 1994 FIPS PUB 196 Entity Authentication Using Public key cryptography Public Key Cryptography 1997 FIPS PUB 197 Advanced Encryption Standard Advanced Encryption Standard ... IEEE P1363 covers most aspects of public key cryptography Transport Layer Security formerly SSL ... Government s cryptography recommendations See also Topics in cryptography Category Cryptography ... more details
Neural cryptography is a branch of cryptography dedicated to analyzing the application of stochastic algorithms, especially neural network algorithms, for use in encryption and cryptanalysis . Definition Neural Networks are well known for their ability to selectively explore the solution space of a given problem. This feature finds a natural niche of application in the field of cryptanalysis . At the same time, Neural Networks offers a new approach to attack ciphering algorithms based on the principle that any function could be reproduced by a neural network, which is a powerful proven computational ... can be used for different aspects of cryptography, like public key cryptography , solving the Key cryptography ... Cryptography and Neural Cryptography. The first work that it is known on this topic can be traced ... of neural cryptography, we improve it by increasing of the synaptic depth L of the neural networks ... name Klimov http cryptome.org neuralsub.ps Analysis of Neural Cryptography by Alexander Klimov, Anton ...?sl fr&tl en&u http 3A 2F 2Fs.dourlens.free.fr 2Fmaitrise 2Fmaitrise.htm Neuro Cryptography 1995 The first definition of the Neuro Cryptography AI Neural Cryptography applied to DES cryptanalysis by Sebastien Dourlens, France. http theorie.physik.uni wuerzburg.de ruttor neurocrypt.html Neural Cryptography Description of one kind of neural cryptography at the University of W rzburg , Germany. http ... Possible practical application of Neural Cryptography. http www.springerlink.com content kbpxkbnkgtk4ymhh Analysis of Neural Cryptography Analysis of neural cryptography in general and focusing ... uni wuerzburg volltexte 2007 2361 Neural Synchronization and Cryptography Andreas Ruttor. PhD thesis ... Kinzel, Rivka Naeh, and Ido Kanter year 2006 title Genetic attack on neural cryptography journal ... Science 2 pages 710&ndash 715 url http www.scipub.org fulltext jcs jcs29710 715.pdf Cryptography navbox Category Theory of cryptography Category Neural networks ru ... more details
unreferenced date September 2009 Image SZ42 6 wheels lightened.jpg thumbnail 320px The German Lorenz cipher machine contained 12 pinwheels, with a total of 501 pins In cryptography , a pinwheel was a device for producing a short Pseudo random number pseudorandom sequence of bit s determined by the machine s initial settings , as a component in a cipher machine. A pinwheel consisted of a rotating wheel with a certain number of positions on its periphery. Each position had a pin or lug which could be either set or unset . As the wheel rotated, each of these pins would in turn affect other parts of the machine, producing a series of on or off pulses which would repeat after one full rotation of the wheel. If the machine contained more than one wheel, usually their periods would be relatively prime to maximize the combined period. Pinwheels might be turned through a purely mechanical action as in the M 209 or electromechanical ly as in the Lorenz SZ 40 42 . Other cipher machines which used pinwheels include the C 52 cipher machine C 52 , the CD 57 and the Siemens and Halske T52 . Pinwheels can be viewed as a predecessor to the electronic linear feedback shift register LFSR , used in later cryptosystems. See also Rotor machine Cryptography navbox machines Category Encryption devices Category Cryptographic hardware crypto stub fr Pinwheel cryptographie ... more details
Unreferenced date June 2009 In cryptography , a boolean function is said to be complete if the value of each output bit depends on all input bits. This is a desirable property to have in an encryption cipher, so that if one bit of the input plaintext is changed, every bit of the output ciphertext has an average of 50 probability of changing. The easiest way to show why this is good is the following consider that if we changed our 8 byte plaintext s last byte, it would only have any effect on the 8th byte of the ciphertext. This would mean that if the attacker guessed 256 different plaintext ciphertext pairs, he would always know the last byte of every 8byte sequence we send effectively 12.5 of all our data . Finding out 256 plaintext ciphertext pairs is not hard at all in the internet world, given that standard protocols are used, and standard protocols have standard headers and commands e.g. get , put , mail from , etc. which the attacker can safely guess. On the other hand, if our cipher has this property and is generally secure in other ways, too , the attacker would need to collect 2 sup 64 sup 10 sup 20 sup plaintext ciphertext pairs to crack the cipher in this way. See also Correlation immunity Category Cryptography crypto stub ... more details
Refimprove date April 2010 In cryptography , a key is a piece of information a parameter that determines the functional output of a cryptographic algorithm or cipher . Without a key, the algorithm would produce no useful result. In encryption , a key specifies the particular transformation of plaintext into ciphertext , or vice versa during decryption . Keys are also used in other cryptographic algorithms, such as digital signature schemes and message authentication code s. Need for secrecy In designing security systems, it is wise to assume that the details of the cryptographic algorithm are already available to the attacker. This principle is known as Kerckhoffs principle only secrecy of the key provides security , or, reformulated as Claude Shannon Shannon s maxim Shannon s maxim , the enemy knows the system . The history of cryptography provides evidence that it can be difficult to keep the details of a widely used algorithm secret see security through obscurity . A key is often easier to protect it s typically a small piece of information than an encryption algorithm, and easier ... being kept secret . Keeping keys secret is one of the most difficult problems in practical cryptography .... The keys used in public key cryptography have some mathematical structure. For example, public keys ... s which aim to have security equivalent to a 128 bit symmetric cipher. Elliptic curve cryptography ... derivation function which adds a Salt cryptography salt and compresses or expands it to the key length ... center Key escrow Key exchange Key generation Key insulated cryptography Key management Key schedule Key server cryptographic Key server Key signature cryptography Key signing party Key stretching Key ... paper key Machine readable paper key Weak key Div col end References references cryptography navbox Interlang Categories Category Cryptography Category Key management bg ca Clau ... Klucz kryptografia pt Chave criptografia ro Cheie criptografie ru simple Key cryptography ... more details
Quantum cryptography describes the use of quantum mechanical effects in particular quantum communication ... of classical i.e., non quantum cryptography to protect against quantum attackers clarify date May 2011 is also often considered as quantum cryptography cn date May 2011 in this case, one also speaks of post quantum cryptography . Well known examples of quantum cryptography are the use of quantum communication ... signature schemes e.g., RSA algorithm RSA and ElGamal . The advantage of quantum cryptography lies ... Hughes and Jane Nordholt title Refining Quantum Cryptography journal Science pages 1584 6 volume ... Main Quantum key distribution Arguably the best known application of quantum cryptography ... is the only example of commercially available quantum cryptography. ref cite web url http www.idquantique.com ... data. Position based quantum cryptography The goal of position based quantum cryptography is to use ... storage model see above . Post quantum cryptography In a predictive sense, quantum computers ... is often referred to as post quantum cryptography. The need for post quantum cryptography arises ... s knowledge, secure against quantum adversaries are McEliece and Lattice based cryptography lattice based schemes. Surveys of post quantum cryptography are available. ref name pqcrypto.org ref ... title Hacking commercial quantum cryptography systems by tailored bright illumination year 2010 publisher ... name thermalblinding cite conference title Thermal blinding of gated detectors in quantum cryptography ... Quantum cryptography Public key distribution and coin tossing booktitle Proceedings of IEEE International ... ref ref name kilian88founding cite conference title Founding cryptography on oblivious transfer first ... first3 Louis last3 Salvail first4 Christian last4 Schaffner year 2005 title Cryptography In the Bounded ... title Post quantum cryptography publisher Springer year 2009 isbn 978 3 540 88701 0 editor first Daniel J. ref ref name pqcrypto.org cite web url http pqcrypto.org title Post quantum cryptography accessdate ... more details
Citations missing date December 2007 Strong cryptography or cryptographically strong are general terms applied cryptography cryptographic systems or components that are considered highly resistant to cryptanalysis . Demonstrating the resistance of any cryptographic scheme to attack is a complex matter, requiring extensive testing and reviews, preferably in a public forum. Good algorithms and protocols are required, and good system design and implementation is needed as well. For instance, the operating system on which the crypto software runs should be as carefully secured as possible. Users may handle passwords insecurely, or trust service personnel overtly much, or simply misuse the software. See social engineering security social engineering . Strong thus is an imprecise term and may not apply in particular situations. Cryptographically strong algorithms This term cryptographically strong is often used to describe an encryption algorithm , and implies, in comparison to some other algorithm which is thus cryptographically weak , greater resistance to attack. But it can also be used to describe hashing and unique identifier and filename creation algorithms. See for example the description of the Microsoft .NET runtime library function Path.GetRandomFileName. ref citation url http ... standard. The term is commonly used to convey that some algorithm is suitable for some task in cryptography ... cryptography makes the job of intelligence agencies more difficult, many countries have enacted law ... export of cryptography beyond a certain strength measured in part by key size , and Russia banned ... people 199504 msg00018.html title nowiki A ban on cryptography in Russia fwd Next .. djf nowiki ... an example of strong cryptography, with versions running under most popular operating systems ... bp 051es.html Strong Cryptography The Global Tide of Change, Cato Institute Briefing Paper no. 51 See also Export of cryptography Category Cryptography ru ... more details
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