The History and Mathematics of Codes and Code Breaking

The Allies’ Teamwork Against the Germans’ Human Error

While the Germans’ overconfidence in the strength of Enigma was a primary factor leading to their loss in the World War II, I believe how the Allies worked in a united and coherent way also significantly influenced the outcome of the battle of cryptography. The French Secret Service first obtained the documents that suggested the wirings of the military Enigma machine, and then handed them to the Poles so that the Biuro Szyfrów could try to crack the Enigma with such a starting point. Furthermore, after the Poles successfully broke the Enigma cipher for several years but were no longer able to decipher the Germans’ messages when more scramblers and plugboard cables were added, they offered their code-breaking techniques to the British and the French, letting them continue the decipherments. Therefore there came the stories at Bletchley Park and Alan Turing’s well-known accomplishments. If any one of France, Poland and Britain was unwilling to share its information and works with others, the Allies might not break the Enigma because no one would have enough resources indispensable to cracking the codes.

In comparison to the Allies’ teamwork, the Germans, interestingly, compromised their own cipher. Germans are always acknowledged as procedural and rigid; with these characteristics they sometimes yielded advantages in the war in which the order and decisive operations mattered. However, their adherence to rules also resulted in flaws in their encryption. The repetition of message keys, and the rigidly structured weather reports were exploited by the Allies to crack the Enigma. Without the human error on the German side, it would take the Allies more time to break the code and end the war.


-Insert Title Here-


Human intellect vs. Machine power

1 Comment

  1. overtocm

    I largely agree with your post. The Allies' sharing of information was the main thing that allowed them to break Enigma, with the Polish government's breakthroughs in the 1920's providing Turing and others at Bletchley Park a foothold to better understand how to exploit Enigma.

    However, your assertion about the Germans compromising their own cipher primarily through their rigidity and adherence to rules seems incomplete. Of course, repeating the key twice and issuing daily weather reports made it much easier for the Allies to break the code, but even after they stopped repeating the message key, code breakers at Bletchley Park were still able to break the code thanks to their ingenuity.

    For example, realizing that no letter could encode to itself that the scramblers could not be arranged in seemingly obvious ways were brilliant insights that allowed the British to exploit other weaknesses (largely due to structure and rigidity) was what allowed the British to decipher Enigma. Of course, the most notable example of this ingenuity is Turing's Enigma Machine which automated the process of cryptanalysis, greatly decreasing the time required to break the code.

    These insights would have been much more difficult to implement (or maybe useless altogether) had the Germans not made mistakes by including structure in the form of weather reports and other repetition that provided the British with cribs, but the ingenuity of the British thanks to the wide variety of backgrounds present at Bletchley Park also played and important role in breaking Enigma.

Leave a Reply

Powered by WordPress & Theme by Anders Norén