双语畅销书《艾伦图灵传》第5章:解谜接力赛(16)

From the cryptanalyst's point of view, however, the physical labours of the cipher clerk, and the physical construction of the machine, were irrelevant.

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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