双语畅销书《艾伦图灵传》第5章:解谜接力赛(162)
No one could speak except on the understanding that what they were saying was being overheard in Berlin.
There was a row in September 1942, when Prince Olaf of Norway had to be refused permission to talk to his five-year-old daughter, lest it set a precedent for the transmission of uncensoRed messages by governments-in-exile.
1942年9月，为了避免挪威流亡政府擅自通信，甚至连奥拉夫王子都不准与他五岁的女儿通话。The essential difficulty of providing speech secrecy lay in the overwhelming redundancy of speech, as compared with writing.
语音加密的困难在于，与文字相比，语音信号携带了过多的不必要的信息，这就使它更容易被破译。
Some efforts were being made at Dollis Hill to create a more sophisticated system, but American developments were much further ahead, and part of Alan's assignment was to investigate them.
电子通信研究所在这方面做出了许多努力，但美国的发展则大幅度领先，艾伦现在的工作，就是去研究他们的技术。It marked a shift from the cryptanalytic to the cryptographic side.
这标志了密码分析领域的巨大改变。Speech secrecy was in another sense also a problem to the British authorities.
语音加密在另一个意义上说，也是英国领导人的一个问题。In 1940 it had not been too difficult: a few jolly clever chaps in a country house were having a go at breaking German codes.
故事是这样的：在1940年，一些聪明的小伙子，在一个乡村的庄园里，愉快地准备破解德国的情报。In 1941 it changed: Churchill was getting the most important information from a source which only a select few knew about.
在1941年，事情发生了变化，丘吉尔通过这个渠道来获得重要的情报，而只有极少人知道，The problem was to throw a ring of secrecy around this mushrooming department which lay outside the normal structure of the state.
所以它成了一个处在国家正常体制之外的秘密小圈子。But by 1942 the problem had changed again. Bletchley Park was no longer outside the ordinary channels: it dominated them.
到了1942年，问题再次变化了，布莱切利庄园不再处于体制之外，反而在其中占了主导地位，几乎成了命根子。There were sixty keysystems broken, producing fifty thousand decrypted messages a month—one every minute.
这里破解了60多个重要的通信系统，每个月破译50000条信息，平均每分钟就有一条。The old days of 'Red' and 'Yellow' were long over and the soaring imagination of the analysts, exhausting the colours of the rainbow, had plundered the vegetable and animal kingdoms:
红机与黄机早就被抛在身后了，他们已经用尽了彩虹的颜色，开始使用蔬菜和动物的名称了：Quince for the SS key, Chaffinch for Rommel's reports to Berlin, Vulture for the Wehrmacht on the Russian front.
党卫军的系统叫雪梨，隆美尔向柏林报告使用的系统叫燕雀，国防军在苏联战线使用的系统叫秃鹫。Certain key-systems were used with the proper safeguards, and with these Bletchley was powerless.
只有个别系统，让布莱切利无能为力，The Shark system, as they called the U-boat key, still remained intact but for those three days in February and March 1942.
比如U艇使用的鲨鱼系统，除了1942年2月和3月的那三天之外，它仍然是无法破译的。But except for these gaps, the German radio communication system had become an open book—to an elite.
除此之外，德国的秘密通信系统，对于这里来说，就是一本敞开着摆在餐桌上的书。
