Cryptography (or cryptology) is a discipline of mathematics and, in modern times, of computer science concerned with information security and related issues, particularly encryption and authentication and other applications such as access control.
Cryptography, as an interdisciplinary subject, draws on several fields. Prior to the early 20th century, cryptography was chiefly concerned with linguistic patterns. Since then, the emphasis has shifted, and cryptography now makes extensive use of mathematics, including aspects of information theory, computational complexity, statistics, combinatorics, and especially number theory. Cryptography is a branch of engineering, but an unusual one as it deals with active, intelligent and malevolent opposition (see cryptographic engineering and security engineering). There is also active research examining the relationship between cryptographic problems and quantum physics (see quantum cryptography and quantum computing).
Cryptography is a central part of the techniques used in computer and network security for such things as access control and information confidentiality. Cryptography is used in many applications that touch everyday life; the security of ATM cards, computer passwords, and electronic commerce all depend on cryptography.
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Snake Oil FAQ - Guide to evaluating the quality and fitness for purpose of cryptography tools.
Meta Description: [ Snake Oil Warning Signs:Encryption Software to Avoid ]
A Cryptographic Compendium - Outline of the various types of cipher systems that have been used historically and the relationships between them.
Adam Back's Homepage: Cypherspace - Find information on some cryptanalytic hacks, breaking weak cryptosystems and links to more cryptography related websites.
An Overview of Cryptography by Gary C. Kessler - Defines cryptographic terms and concepts, offers crypto scheme comparison, and provides some real world examples.
Choosing a Good Password - Tips on choosing a difficult to crack password and pitfalls in password selection.
Meta Description: [ Choosing a Good Password> ]
Coderpunks - Little sister of the cypherpunk mailing list. Discussion of implementations of strong, robust cryptosystems.
Crypto Machines - Features machines and systems used in secure communications. Includes brief history on cryptography.
Crypto-Gram - Free monthly email newsletter covering developments in cryptography and other computer security issues.
Cryptography FAQ - Ten part FAQ list that is essential reading for any newcomer to cryptography.
Cryptography World - Introduction to cryptography, including concepts, key management and application.
Meta Description: [ Cryptography Introduction: Generic source for Encryption, Decryption and Key Management ]
CryptoMX Tools - Set of cryptography tools written entirely in JavaScript, designed to work on any computer with a JavaScript capable browser.
Cryptonomicon - Cryptography related articles, downloads, news, links and discussions.
Cyphernomicon - Tim May's CryptoNotes, and an introduction to the Cypherpunks.
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Cypherpunks - Group, with mailing list, that is interested in privacy and cryptography.
Deschall - Articles describing the first crack of a DES-encrypted message, with some source code and mailing list archives.
Frode Weierud's Cryptology Page - History of cryptography, cipher machines and their simulation, cryptanalysis and other code breaking techniques.
Meta Description: [ Frode's Cryptology Page is dedicated to the history of cryptography, cipher machines and
their simulation, cryptanalysis and other code breaking techniques. ]
Handbook of Applied Cryptography - Reference work available for free download (with restrictions) from the Web.
Meta Description: [ This site provides order information,
updates, errata, supplementary information, chapter bibliographies,
and other information for the Handbook of Applied
Cryptography by Menezes, van Oorschot and Vanstone. ]
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Home of HB9CUF - Free cryptographic tools: CryptoUP to secure and transport any kind of file; FindSR helps to analyze ciphertext.
Meta Description: [ Download: CryptoUP - crypto utility for any kind of file. FindSR - a bitlevel analyzer for encrypted data. ]
International Association for Cryptologic Research (IACR) - Non-profit scientific organisation intended to further research in cryptology.
International Cryptography Freedom - Links to cryptography related downloads and information from around the world.
MD5 Reverse Lookup - Project to record and search for mappings of MD5 hashes to their original messages.
Randomness and the Netscape Browser - Article about cracking the original Netscape encryption algorithm, and links to resources for generating crypto strength randomness.
RSA - Hacking and Cracking - Discusses security problems and possible attacks against the RSA cryptosystem.
Meta Description: [ A collection of pages discussing RSA and attacks on the system ]
Standard Cryptographic Algorithm Naming - Provides references for a collection of cryptographic algorithms, assigning each an ASCII name and zero or more aliases.
Strong Cryptography Links on the Internet - Dealing with cryptography, information security, cryptographers government, commercial, university, and personal sites, newsgroups, publications, programs and applications.
Meta Description: [ This page contains links and pointers to other web pages dealing with
cryptography and information security, Strong Cryptography, Blowfish, DES, c2 Net, DigiCash, Cybercash,
Cryptography and Security, IEEE, NSA, Applied Cryptography, Information Security, Prime Numbers, RC5-64,
distributed.net,... ]
The Cipher Challenge - History of a code cracking competition. Challenge details, how it was solved, winners, essays and photo gallery.
Meta Description: [ The home of Simon Singh - author, journalist and TV producer, specialising in science and mathematics. ]
The Munitions Maker Graphic - Campaign to distribute image (rsa2d.gif) in protest of ITAR regulations that treat encryption as munitions.
Why Cryptography Is Harder Than It Looks - Essay on pitfalls of implementing and using secure systems.
| Cryptography Documentary |