Cryptography standards

There are a number of 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)
 * Advanced Encryption Standard (AES)
 * RSA the original public key algorithm
 * OpenPGP

Hash standards

 * MD5 128-bit (obsolete)
 * SHA-1 160-bit (obsolete)
 * 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
 * Elliptic Curve DSA

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 * Wired Equivalent Privacy (WEP), severely flawed and superseded by WPA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 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 (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 DES Modes of Operation 1980
 * FIPS PUB 102 Guideline for Computer Security Certification and Accreditation 1983
 * FIPS PUB 112 Password Usage 1985, defines 10 factors to be considered in access control systems that  are based on passwords
 * FIPS PUB 113 Computer Data Authentication 1985, specifies a Data Authentication Algorithm (DAA) based on DES, adopted by the Department of Treasury and the  banking community to protect electronic fund transfers.
 * FIPS PUB 140-2 Security Requirements for Cryptographic Modules 2001, defines four increasing security levels
 * FIPS PUB 171 Key Management Using ANSI X9.17 (ANSI X9.17-1985) 1992, based on DES
 * FIPS PUB 180-2 Secure Hash Standard (SHS) 2002 defines the SHA family
 * FIPS PUB 181 Automated Password Generator (APG) 1993
 * FIPS PUB 185 Escrowed Encryption Standard (EES) 1994, a key escrow system that provides for decryption of telecommunications when lawfully authorized.
 * FIPS PUB 186-2 Digital Signature Standard (DSS) 2000
 * FIPS PUB 190 Guideline for the Use of Advanced Authentication Technology Alternatives 1994
 * FIPS PUB 191 Guideline for the Analysis of local area network Security 1994
 * FIPS PUB 196 Entity Authentication Using Public Key Cryptography 1997
 * FIPS PUB 197 Advanced Encryption Standard (AES) 2001
 * FIPS PUB 198 The Keyed-Hash Message Authentication Code (HMAC) 2002

Classified Standards

 * EKMS NSA's Electronic Key Management System
 * FNBDT NSA's secure narrow band voice standard
 * Fortezza encryption based on portable crypto token in PC Card format
 * STE secure telephone
 * STU-III older secure telephone
 * TEMPEST prevents compromising emanations

Other

 * IPsec Virtual Private Network (VPN) and more
 * IEEE P1363 covers most aspects of public-key cryptography
 * Transport Layer Security (formerly SSL)
 * SSH secure Telnet and more
 * Content Scrambling System (CSS, the DVD encryption standard, broken by DeCSS)
 * Kerberos authentication standard
 * RADIUS authentication standard
 * ANSI X9.59 electronic payment standard
 * Common Criteria Trusted operating system standard
 * CRYPTREC Japanese Government's cryptography recommendations