双语畅销书《艾伦图灵传》第5章:解谜接力赛(16)
日期:2018-01-02 17:12

(单词翻译:单击)

From the cryptanalyst's point of view, however, the physical labours of the cipher clerk, and the physical construction of the machine, were irrelevant.
然而,从密码分析的角度来看,密码操作员的工作量与机器的物理结构无关,
What mattered was the logical description, just like a Turing machine.
而是在于它的逻辑原理——就像图灵机。
Everything relevant to the Enigma was contained in its 'table', a list of its states and what it would do in each state.
谜机的一切,都可以体现在一个行为表中,这张表描述了它的每个状态,以及在每个状态下会做什么。
And from a logical point of view, the action of the Enigma, in any given, fixed, state, enjoyed a very special property.
从逻辑的角度上看,谜机在任何一个给定的状态下,都会执行一种特定的动作。
It was a symmetrical property inherent in the 'reflecting' nature of the machine.
这是机器的“反射”性质固有的对称性质。
For any Enigma, in any state, it would be true that if A were enciphered into E, then in that same state, E would be enciphered as A.
对于一台谜机,无论在任何状态下,如果它将A替换成E,那么在同样的状态,E就会被替换成A。
The substitution alphabets resulting from an Enigma state would always be swappings.
谜机的替换表,实际上是一种对换。
For the hypothetical 8-letter machine in the state shown in the first diagram, the substitution would be:
我们前面假想的8字母机,在第一幅图的状态下,替换规则是:
plain A B C D E F G H
明文ABCDEFGH
cipher E D G B A H C F
密文EDGBAHCF
For the machine in the state shown in the second diagram, it would be:
在第二幅图的状态下,则是:
plain A B C D E F G H
明文ABCDEFGH
cipher E F G H A B C D
密文EFGHABCD

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