‘The Imitation Game’ is a dramatisation of the British efforts to break encrypt German military communications in time to change the course of WW2.
In Part One of this four part series, I began my discussion of ‘The Imitation Game’.
Alan Turing and his fellow British cryptologists were dedicated to breaking the Enigma code, the method of encrypting German military communications.
The German Enigma code was based upon portable cipher machines with rotary scramblers, with some visual similarities to a typewriter. Encoded messages were generated using the cipher machines before transmission. The rotary scramblers were intended to create millions of possible encoding keys, determined daily by pre-arranged encryption instructions. Authorised recipients of the messages used the pre-arranged instructions to determine the applicable settings and decipher the message. In theory, the codes were unbreakable due to the sheer number of possible encryption settings. However, due to poor operational practices by individual German operators, Allied cryptologists became aware of re-occurring patterns with the scrambler settings. The German military used Enigma machines throughout WW2, unaware that Allied cryptologists were deciphering their messages.
Alan Turing developed a cryptanalytic machine, an early computer that could analyse the likely scrambler settings used on a given day and decipher individual messages. The sloppy German cryptology procedures served to reduce the number of possible combination of settings sufficiently for the cryptanalytic machines to complete their analysis of the possible settings and decode the messages within the daily time-limit before the settings were re-set.
However, as the film points out, knowing a secret is not enough. Once you know a secret, you must keep the secret that you know the secret. If the Allies acted on every deciphered message, such as the time and place of every individual U-Boat attack on an Allied convey, the German military would immediately become aware that their code had been broken. The inevitable consequence would be a change of code, leaving the Allies ignorant once again of the meaning of the German codes. Therefore, Turing and his team had to live with the guilt that they knew in advance that Allied lives were going to be lost.
In Part Three of this four part series, I will discuss the personal cost of the multitude of military and personal secrets maintained during the film.
Photo Copyright Details:
|Title: The_Imitation_Game_poster Description: This is a poster for The Imitation Game. The poster art copyright is believed to belong to the distributor of the film, the publisher of the film or the graphic artist. Date: not dated Source: Wikipedia Commons The poster art copyright is believed to belong to the distributor of the film, the publisher of the film or the graphic artist. However, this low resolution image is reproduced with the intention of providing a commentary on the film.|