| 翻訳と辞書 |
EFF DES cracker
In cryptography, the EFF DES cracker (nicknamed "Deep Crack") is a machine built by the Electronic Frontier Foundation (EFF) in 1998, to perform a brute force search of DES cipher's key space – that is, to decrypt an encrypted message by trying every possible key. The aim in doing this was to prove that DES's key was not long enough to be secure.
==Background==
DES uses a 56-bit key, meaning that there are 256 possible keys under which a message can be encrypted. This is exactly 72,057,594,037,927,936, or approximately 72 quadrillion possible keys. One of the major criticisms of DES, when proposed in 1975, was that the key size was too short. Martin Hellman and Whitfield Diffie of Stanford University estimated that a machine fast enough to test that many keys in a day would have cost about $20 million in 1976, an affordable sum to national intelligence agencies such as the US National Security Agency.〔(【引用サイトリンク】title=DES (Data Encryption Standard) Review at Stanford University - Recording and Transcript )〕 Subsequent advances in the price/performance of chips kept reducing that cost until twenty years later it became affordable to even a small nonprofit organization such as EFF.〔https://w2.eff.org/Privacy/Crypto/Crypto_misc/DESCracker〕
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「EFF DES cracker」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|