The Hut Six Story : Breaking the Enigma Codes

Here we have a publication that takes you deep within the code-breaking fortress of Bletchley Park – and some!Told by a very modest man at the very top of his game, this publication is filled with VALUABLE WARNINGS about the subversive clandestine EVER PRESENT threats that surround us, and how prolonged secrecy has been prejudicial to Britain’s advancement and wealth in the computer race, as well as posing a serious threat to national security.Here Gordon Welchman OBE sends out a clear warning – much needed today – that we must NOT neglect the NONMILITARY means by which an enemy may seek to UNDERMINE OUR NATIONAL WILL by using our rapidly advancing technology AGAINST us and we must ALWAYS be in a constant state of PREPAREDNESS.Taking the reader on a wonderful thrilling journey of enlightenment, Gordon Welchman poses the question ‘will the security measures we plan today be adequate in the technological environment of tomorrow?’ as he examines the ‘special means’ enemies consistently deploy to undermine the well-being of our society such as infiltration by hacking, sabotage, theft, jamming, and spoofing, before taking us deep within the clandestine operations and methods that smashed through a machine-generated cipher that was allegedly ‘uncrackable’.Here we learn about how a freely-available BRITISH publication on ‘the art of war’ that Gordon Welchman considered was ‘too risky to be let out’ was obtained ten years later by Adolph Hitler – who then re-invented his military might to utilise the techniques the publication contained – with DEVASTATING results – results that took TWO NUCLEAR BOMBS to appease!Educated at Trinity College, Gordon Welchman then provides a WONDERFUL explanation of how the Enigma machine functions to scramble the plaintext into (seemingly) gibberish, and how re-entering the transmitted ‘gibberish’ at the receiving end revealed the plaintext, before modestly describing how his imaginative attack on the TENS OF BILLIONS of POSSIBLE permutations – permutations that were instigated by the SENDER at his own whim - can be reduced to a MILLION or so by exploiting a very simple mathematical principle based upon the MATHEMATICAL RELATIONSHIP of two DICE.As you are keenly interested, permit me to explain.Simply put: given a six-sided die with each side numbered one through six, the ODDS of throwing any given value is ALWAYS one CHANCE IN SIX on each and every throw.Put another way, the odds of NOT throwing the ‘wanted’ value is FIVE chances in SIX on each and every throw – and this can be exploited in a very clever way.Given TWO dice – each die numbered one through six - the ODDS of throwing any given value is ALWAYS ONE chance in six on the first die MULTIPLIED by ONE chance in six on the SECOND die – giving a ONE CHANCE IN THIRTY SIX of throwing the ‘wanted’ value on each and every throw - and a thirty-five to thirty six chance of NOT throwing the ‘wanted value’ on each and every throw. This is what the encryption method relied uponHOWEVER - the VALUE of the FIRST dice thrown ELIMINATES a HUGE amount of PROBABILITIES.If one was to throw (say) a FOUR on the first die, the ONLY numbers available are based upon on the AVAILABLE VALUES of the SECOND die.In my example these are:Die one = 4 and die two = 1 = 4+ 1 = 5;Die one = 4 and die two = 2 = 4+ 2 = 6;Die one = 4 and die two = 3 = 4+ 3 = 7;Die one = 4 and die two = 4 = 4+ 4 = 8;Die one = 4 and die two = 5 = 4+ 5 = 9;Die one = 4 and die two = 6 = 4+ 6 = 10;Hence the numbers 2, 3, 4, 11 and 12 are NOT POSSIBLE if the first die lands on a FOUR – so a HUGE hole is smashed in the number of PROBABLE permutations (in the case of two dice = 36 - from double one through to double six) to just SIX POSSIBLE permutations – in this example - five through ten (representing just six POSSIBLE letters in THAT position).Try it! Throw a die; look at the number on the top face; and now PREDICT the values of the two dice BEFORE you throw the second die – and watch 36 of the PROBABILITIES disappear to just SIX POSSIBILITIES.Having done that, throw the second die to see which one of your six predictions ‘turns up’.The next level of attack is to take each of the six possibilities at each position and look at successive letter pairings – this time looking for letter sequences that are gobbledegook – for example - using words in the English language – in any given word, the letter ‘P’ cannot be followed by the letter ‘D’, or the letter ‘F’, or the letter ‘G’, or the letter ‘J’ and so on – and so letters could be swiftly ELIMINATED because their SEQUENCE did not make any sense. This is akin to playing ‘word search’.THAT dear reader is the basic premise of how Gordon Welchman and his team attacked the Enigma – and regularly ‘cracked’ it – except he was dealing with three ‘26 sided’ ‘dice’ – the alphabetic scrambling rotors in the machine – two of which were ‘thrown’ and remained on ‘hold’ - and one which would be ‘nudged’ for 26 ‘attempts’ – with each ‘held’ dice (rotor) AUTOMATICALLY reducing the number of POSSIBLE permutations in the manner I have illustrated – just like ‘playing’ a ‘fruit machine’ using ‘hold’ and ‘nudge’ – except you could not see the fruits – or COULD you? Read the fascinating insightful book and find out HOW you could ‘see’ the hidden fruits (and much much more besides).The ciphertext was considered to be ‘cracked’ by a person – and ‘hacked’ by Turin’s ‘computable machine’ (called a bombe) – thousands of which were deployed to swiftly find the solutions to the HUGE volume of traffic - detected from as far away as Stalingrad using a very sensitive radio receiver known as a TRF that doesn’t ‘reveal’ itself on the ether – unlike a ‘superhetrodyne’ receiver – which DOES – which was gainfully exploited to eavesdrop, and is now gainfully exploited to detect reception of unlicensed TVs (and tell you which TV channel you were watching at the time that they book you – tee hee).Of course SPEED of decoding is of the essence if one is to make use of the information obtained, so as to be able to swiftly intercept the enemy and strike a huge blow first - or take decisive and effective evasive action – action that saved MILLIONS of lives and tipped the balance from failure to success against all of the ODDS. To bring speed to the process required a HUGE technological leap – a technological leap that changed the world FOREVER!If you wish to discover the inner-workings of an Enigma machine and see how such a formidable cipher was swiftly cracked in a matter of weeks by the melding of two minds – the mathematical genius of Gordon Welchman and his powerful ‘method of attack’ on Enigma - who joined forces with another British mathematical genius - ALAN TURIN - which led to Turin inventing the COMPUTER – then THIS masterwork is for YOU!If you wish to see the huts for yourself, and see demonstrations of the REAL working equipment, and meet and shake the hands of the REAL people who worked on cracking and hacking Enigma, then visit BLETCHLEY PARK in Bletchley - and be AMAZED!

Good story...bit technical in places

I really enjoyed this. It is "lightly" written, nice and bouncy, cheery. But, I have a PhD in Computer Science so maybe I am no judge of this

It won’t thrill you, it won’t make you laugh, it won’t make you cry. If you have an interest in the subject matter, what it will do is fill you with admiration and wonder at what the (perhaps long lost) British psyche is capable of in the face of a daunting adversary.This book has relevance today, make no mistake about that. The Bletchley Park crew are and always will be 24 carat heroes.

Very interesting slice of history. Very thin margins between death and survival during WW2.

I found the story very interesting, although much of the mathematical explanation of how breaks were achieved passed way over my head. The inclusion of a separate, but related article written later was a bonus feature but included some duplication. Some may not particularly like the photo-like typeface.

Some of the detail is difficult to understand but worth the effort to gain an understanding of the author's contribution to cracking the German coding system.

This is about Station X and a man directly involved in breaking the codes . The way he deciphered the codes is very difficult to follow, but his life history is interesting. the sad point is what the Military Industrial Complex can do to you if you step out of line