作者woody3724 (woody)
站内Prob_Solve
标题[问题] 密码学 3DES 中间的步骤为何用decryption
时间Fri Mar 28 22:48:07 2014
密码学
3DES的加密三个步骤是
E(加密) -> D(解密) -> E(加密)
原文书题到 (以下英文撷取自课本原文书)
There is no cryptographic significance to the use of decryption for the second
stage of 3DES encryption. Its only advantage is that it allows users of 3DES
to decrypt data encrypted by users of the older single DES:
C = E( K1,D( K1,E( K1, P ) ) ) = E[K,P]
where C = ciphertext
P= plaintext
E[K,X] = encryption of X using key K
D[K,Y] = decryption of Y using key K
看完这段还是不懂为什麽中间的步骤要用解密
尤其是older single DES不懂
谢谢
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1F：推 suhorng:因为key取一样就可以变 (1)DES 03/28 22:53
2F：→ suhorng:一种电路,两种用法,赚! 03/28 22:53
3F：→ woody3724:感谢楼上!!!! 03/29 16:18