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des [2021/07/26 17:50]
spencer created
des [2021/07/26 17:51] (current)
spencer
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-DES +====== DES ====== 
-INTRO+ 
 +===== INTRO ===== 
 The Data Encryption Standard (DES) is a touchstone symmetric block cipher which has been used The Data Encryption Standard (DES) is a touchstone symmetric block cipher which has been used
 worldwide since it was published in 1975 in the U.S. Federal Register. It has remained unchanged since worldwide since it was published in 1975 in the U.S. Federal Register. It has remained unchanged since
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 bits. This setup has not aged well, and the cipher has been superseded by the Advanced Encryption bits. This setup has not aged well, and the cipher has been superseded by the Advanced Encryption
 Standard (AES). Standard (AES).
-HISTORY+===== HISTORY ===== 
 While in a partnership with Lloyds Bank in the United Kingdom, IBM’s cryptographer Horst Feistel While in a partnership with Lloyds Bank in the United Kingdom, IBM’s cryptographer Horst Feistel
 headed a development team called project ‘Lucifer’ in the 1960s. The goal of the endeavor was to create a headed a development team called project ‘Lucifer’ in the 1960s. The goal of the endeavor was to create a
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 shortened key size would be a major detriment, eventually leading to the request from NIST in 1997 for a shortened key size would be a major detriment, eventually leading to the request from NIST in 1997 for a
 new algorithm to formally replace DES. new algorithm to formally replace DES.
-BASIC DESCRIPTION+===== BASIC DESCRIPTION ===== 
 Like all bock ciphers, DES is created in such a way that a block of plain text will be employed to create a Like all bock ciphers, DES is created in such a way that a block of plain text will be employed to create a
 cipher text block of the same size. The two parties employing the cipher will share the encryption key. For cipher text block of the same size. The two parties employing the cipher will share the encryption key. For
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 format are called Feistal Ciphers, including DES. This family of algorithms revolves around a specific format are called Feistal Ciphers, including DES. This family of algorithms revolves around a specific
 function which can be either highly complex or simplistic, and is generally known by the shorthand ‘F’. function which can be either highly complex or simplistic, and is generally known by the shorthand ‘F’.
-WEAKNESSES+===== WEAKNESSES ===== 
 In January of 1999, the worries of Whitfield Diffie and Martin Hellman were officially proven to be true. In January of 1999, the worries of Whitfield Diffie and Martin Hellman were officially proven to be true.
 DES was broken by the Electronic Frontier Foundation’s DES cracker (nicknamed "Deep Crack") in 22 DES was broken by the Electronic Frontier Foundation’s DES cracker (nicknamed "Deep Crack") in 22
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 modified by the NSA to be resistant to differential cryptanalysis, however it has not been strengthened modified by the NSA to be resistant to differential cryptanalysis, however it has not been strengthened
 against Linear cryptanalysis, an Improved Davies' Attack or Differential-Linear cryptanalysis. against Linear cryptanalysis, an Improved Davies' Attack or Differential-Linear cryptanalysis.
-VARIATIONS+===== VARIATIONS ===== 
 Most single incarnations of DES were replaced with the more robust Triple DES, a derivation of the Most single incarnations of DES were replaced with the more robust Triple DES, a derivation of the
 original form. Triple DES is far more secure than the original DES, however, it too suffered from a short original form. Triple DES is far more secure than the original DES, however, it too suffered from a short
des.txt · Last modified: 2021/07/26 17:51 by spencer