双语畅销书《艾伦图灵传》第5章:解谜接力赛(23)
They had not broken the machine; they had beaten the system.
The basic principle of using an Enigma machine was that its rotors and rings and plugboard would be set up in some particular way,
谜机的基本原理是，将它的转盘、带子和配线板，设定到某个选定的初始状态，and then the message would be encrypted, the rotors automatically stepping round as this was done.
然后就可以对信息进行编码，它的转盘会自动旋转步进。
But for this to be of any use in a practical communication system, the receiver of the message also had to know the initial state of the machine.
在实际的通信系统中，信息的接收方必须知道那个选定的初始状态。It was the fundamental problem of any cipher system.
这是所有密码系统都面临的一个问题。The machine was not enough; there had to be also an agreed, fixed, 'definite method' of using it.
光有机器是不够的，还需要有确定的、固定的、约定的方法来使用它。According to the actual method employed by the Germans, the initial state of the machine was partly decided at the time of use by the cipher clerk.
德国在实践中的作法是，机器的初始状态部分取决于执行操作的时间。Inevitably, therefore, it made use of indicators, and it was through the indicator system that the Poles enjoyed their success.
因此，它必须要利用指示信号，而波兰正是利用指示信号而获得成功的。To be explicit, the order of the three rotors was laid down in written instructions, and so was the plugboard and ring-setting.
确切来说，操作指南中讲解了三个转盘的次序，配线板以及带位设定。The task of the cipher clerk was to choose the remaining element, the initial settings for the three rotors.
密码操作员的工作，就是为三个转盘设定初始盘位。
