It was in this aspect of the Delilah that his cryptanalytic experience came into play.
在这个特性上，他的经验发挥了作用。
The work they had done so far constituted the mechanism for 'adding on' to speech.
他们目前为止所做的工作，都没有脱离叠加机制，
The crucial question of what to add was the one on which he had spent much of his time since 1938.
而图灵从1938年就开始思考一个更关键的问题，那就是要叠加什么。
In this he could act as the mathematical Cambridge and Bletchley figure, rather than someone who had joined in, somewhat awkwardly and embarrassingly, with the expanding world of electronic engineering.
在这个问题上，他终于可以扮演剑桥数学家，或者来自布莱切利的人物了，而不是一个有点笨手笨脚的尴尬的业余电子工程师。
Although he could not say, nor even hint, the task amounted to creating something like the Fish key generator.
这项工作相当于设计一个类似于鱼机密钥产生器的东西。
It had to be deterministic, for otherwise it could not be produced identically at two independent ends.
它必须有确定的工作过程，否则就无法在两个独立端产生一致的密钥。
But it had to be sufficiently devoid of pattern or repetition, to be as secure as something truly 'random', such as electronic noise.
但它又必须避免规律或重复，然后才能像随机密钥一样安全，比如电子噪声。
Any kind of mechanism would, inevitably, have some pattern to it; the job was to make sure that it was one that the enemy cryptanalyst could not possibly detect.
然而，任何一种机器都不可避免地会存在一些规律，他们的工作就是找到一套敌方密码分析员无法识破的规律。
So in doing this for the Delilah, he was finally scoring off the half-hearted efforts of German cryptography.
在这项工作中，图灵战胜了三心二意的德国密码部门，
In fact, he was doing very much better, for the Delilah key would have to be supplied in sequences of hundreds of thousands of numbers.
他了不起的地方在于，黛丽拉的密钥是个具有成千上万项的数列，这跟加密电报信息是不一样的，
It was like enciphering not telegraph messages, but War and Peace.
相比之下更像是加密一整本《战争与和平》。