Fascinating.
Thanks for this!
Did the Germans ever got clued up that their supposedly encrypted message system have been compromised?
El Reg had the honour of speaking with a war hero last Friday when the UK's National Museum of Computing fired up its replica Enigma code-breaker to decrypt messages sent from Poland. Ruth Bourne was among hundreds of Wrens who worked on the front line of code-breaking on 200 or so Bombe machines1 at sites in and around …
As I understand it, the Germans received a couple of hints that codes might have been cracked. At one point they went back and interviewed the polish codebreakers they captured who had cracked Enigma before the war but the poles were able to convince the Germans that changes in procedures meant the same cracking shortcuts they used were no longer possible.
On more than one occasion I think they reviewed the information they had and convinced themselves that it was still uncrackable , rather than erring on the side of caution as the allies often did.
Did the Germans ever got clued up that their supposedly encrypted message system have been compromised?
Apparently their techies always believed that it was impossible.
Other people had their suspicions. That's why Doenitz - head of the Navy, including U-boats - changed the Naval Enigma in February 1942, from a 3-rotor to a 4-rotor machine, with the result that BP was unable to decrypt the crucial U-boat traffic for nearly a year afterwards.
"BP was unable to decrypt the crucial U-boat traffic for nearly a year afterwards."
Even when unable to decrypt the traffic, the transmission themselves provided a shitload of useful metadata - RDF fixes on the origin coupled with each operator having a unique "fist" meant that they roughly knew where the subs were, etc.
Curiously, the Italians believed the Allies were reading Enigma traffic during the North African campaign. They found that a single scout plane spotting supply ships consistently in the Mediterranean Sea was too big a coincidence.
The German Navy was worried about decrypts after suffering from the UK successes in WWI. German naval cryptologists added a 4th wheel to Enigma and tightened up operating standards.
It might help that Wilhelm Canaris, head of the Abwehr (German Military Intelligence) is rumoured to have been a double agent.
German naval cryptologists added a 4th wheel to Enigma
That only effectively added a second 'reflector' [0] to the unit, and while that added cryptological complexity it was way less than the Germans thought it would. Every keystroke moved the rightmost wheel, then on one full rotation it moved the next one on the left, etc. So the fourth wheel hardly ever moved unless they had a very long message, and only its internal wiring and the starting position added to the coding.
[0] a disc to the left of the rotors, wired so that a current through the rotor wiring got routed back through the rotors again and to the 'display', a field of small lightbulbs displaying the (de)coded character for the pressed key. This made that the coding and decoding could be done on the same device with matching rotors and starting setting.
Neal Stephenson wrote a great book about the period (amongst another story set in modern times), in the Cryptonomicon.
Made that point precisely about having to not get 100% but also to give the Axis forces enough clues to think other means were the reason the Axis losses occurred.
Did the Germans ever got clued up that their supposedly encrypted message system have been compromised?
R.V.Jones' Most Secret War refers to this dilemma: acting on information versus keeping the fact that the code was broken under wraps. In some cases where acting was the strongly preferred option because of the anticipated consequences of not acting, a 'thank you for the info' was sent to a (non-existent) agent who could have plausibly provided the pertinent info.
British wartime intelligence went to great lengths to keep the secret. The high command even (as mentioned above, and downvoted for some reason) sometimes refused to act on Ultra intel, because they felt it could blow the gaffe.
There were some close calls, and the Germans must have had suspicions from time to time, but never to the point of acting on them, at least not concertedly and effectively.
Heck, if they'd just stopped saying "Heil Hitler" in every other message, that alone would have made the job significantly harder.
I'm presuming that formal official messages would have been composed in Standard German (or the equivalent of the time) with the stilted jargon which permeates organisations. Would there have been other messages -- banter between operators -- in dialect or vernacular German?
I think I read somewhere that elements of "personalisation" in the source messages did come into it. Each operator had their own keying style, so the interceptors knew who it came from, and certain operators would have little quirks in their message content.
Real needle-in-a-haystack stuff though, nevermind the complexity of the encyphering of the message.
I've read a few books and watched a few documentaries about this subject over the years, so in theory I kind of understand the principles....but of you gave me an Enigma-encoded message I honestly wouldn't know where to start. Very much hats off to everyone involved at Bletchley Park.
"I think I read somewhere that elements of "personalisation" in the source messages did come into it. Each operator had their own keying style, so the interceptors knew who it came from, and certain operators would have little quirks in their message content."
Yes, this was a known "feature" of telegraph operators almost from the invention of the telegraph. There many stories around of telegraph operators knowing who was "calling" from way the Morse was tapped out. No doubt any Ham operators still using Morse have the same experience today with their regular contacts.
Would there have been other messages -- banter between operators -- in dialect or vernacular German?
I know that as well as looking for "Heil Hitler", details of the weather, and similar stuff - one look-out post sent "Nothing to report" day after day, using different keys, a godsend for the codebreakers - some of the operators used to talk about their girlfriends. So the codebreakers would look for the girlfriend's name - and I'm sure that some of these messages would certainly have used the vernacular!
I know that as well as looking for "Heil Hitler", details of the weather, and similar stuff - one look-out post sent "Nothing to report" day after day, using different keys, a godsend for the codebreakers
And having established which look-out post sent this same very useful "nothing to report" message every day it was decided that the disturbance of the people in it might lead to a different report being sent, so the people in this look-out post had a very, very quiet war.
I found it!
The German radioman who always transmitted 'nothing to report' was stationed in the Qattara Depression in North Africa, in case the Allies tried bringing a whole army through impassable terrain.
Cite: wikipedia.org: Qattara_Depression#World_War_II
I found this thanks to Lindybeige, who mentioned it in an otherwise-only-tangential video relating to Great British Wartime Deceptions: youtube: watch?v=6ZYadpxoUbc
one look-out post sent "Nothing to report" day after day, using different keys,
The Wehrmacht (army) had some 40.000 Enigmas in use, and more than once a sloppy operator accidentally sent today's first message with yesterday's setting, then resent it with today's. If yesterday's code was already broken, then so was that day's. And if not, it certainly helped. Repeating a particular message, with some words abbreviated the second time, that the intended receiver hadn't been able to copy down correctly also offered cracking advantages.
The Kriegsmarine had way less devices and operators, and much tighter code discipline as well.
I remember seeing one documentary, and it mentioned that they noticed that one encrypted message had no "L"s in it. As the machine always changed the letters type in, they came to the conclusion that the message sent was something like -
LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
- or similar
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but I don't think the Poles who got things rolling are given their due.
They most certainly are appreciated and given their due respects within those folk that follow the Bletchley Park story, and by Bletchley Park itself.
It's Hollywood history that neglects them, and quite a lot of other stuff too.
"Of course the heros of Bletchley Park are rightly lauded, but I don't think the Poles who got things rolling are given their due."
FWIW, ever since I first heard of all this, pretty much every story has included mention of the Poles and how the British built on their knowledge.
I remember seeing one documentary, and it mentioned that they noticed that one encrypted message had no "L"s in it. As the machine always changed the letters type in, they came to the conclusion that the message sent was something like -
LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
I didn't know we'd been spying on the Welsh during WWII
First, thanks to El Reg, and to Ms Bourne, for this very interesting piece. These stories from people who were there are now, sadly, almost impossible to get.
Second, my late mum did this in Washington as a WAVE. She never really got into detail about what she did and whose codes she worked on, and we didn't think to grill her, but she could recite the alphabet backwards and always did the crossword in the morning with her coffee.
But my (virtual) hat is off to those like Ms Bourne, who did this work while in England, where everything was scarce, there was a constant danger of bombs, and the threat of invasion. Well done, ma'am, and thank you for your service!
Greatest Generation, indeed...they did more with less, and didn't complain about it.
To pretty much all of the people that did those things, they were just doing their job.
At the end of the day, they didn't have much choice in the matter, if they didn't do it then there was a good chance the country would have been invaded, and besides, if you're called up then your only choice is doing the work or going to jail (and having to do worse work).
>She never really got into detail about what she did and whose codes she worked on, <
The IEEE published memories from a Washington WAVE ('we joined the navy to see the world, but all we saw was DC'). She reported that after a strict security introduction, another man got up. They expected the good cop after the bad cop. Instead they got the worse cop: "DON'T EXPECT THAT YOU WILL BE TREATED ANY DIFFERENTLY BECAUSE YOU ARE WOMEN. IF YOU TALK ABOUT YOUR WORK, YOU WILL BE SHOT."
So true, I found out just last year after he had died that my father-in-law was one of the intercept operators stationed just outside of Loughborough in the midlands.
Real shame as I would have liked to know more.
"Second, my late mum did this in Washington as a WAVE. She never really got into detail about what she did and whose codes she worked on, and we didn't think to grill her, but she could recite the alphabet backwards and always did the crossword in the morning with her coffee."
If you've not yet seen it, you might enjoy both series (seasons) of The Bletchly Circle, a sort of detective story where the heroines are Bletchly almumin using their skills to solve the case, the second series being set when two of them follow a lead to the US and meet one of their opposite numbers who they only knew through a code name and telegraph messages.
It's not really directly related to this story of course, but shows a little of how women who were important and doing vital war work were often "pushed back into the kitchen" after it was over.
"I think I read somewhere that elements of "personalisation" in the source messages did come into it. Each operator had their own keying style, so the interceptors knew who it came from, and certain operators would have little quirks in their message content."
Yes this was used to generate individual cribs:-
- Operators sending messages to be passed on to girlfriends etc
- Standard form test messages that they were too lazy to alter as they were meant to.
- Returned test messages to check for clarity of transmission and retransmission
- Requisitions of stores and stocks were another good one. If you got a message from a fuel dump they would report stock levels periodically at a known time each week etc.
- And the well known weather and HH (I don't even want to type those two words) cribs
And the list get pretty big but one you know the 'touch' of the operator you could look for a likely crib in the decrypts.
Obviously you focus on the operators who spew out cribs with standard form messages at known times.
There are actually two types of "personalization." The first has been mentioned a couple of times, the habits of certain individuals to compose messages the same way. I especially enjoyed the "Nothing to report" standard message as being a good crib.
The other type of personalization was the Morse code sending itself. (Being an old ham radio operator, I speak from experience.) Every Morse code operator has his, or her, own rhythm. The weight (length) of the dots and dashes vary from person to person. With practice the interceptor learns to recognize the rhythm, sometimes called "the fist," of certain operators. Joe's code sending definitely sounds different than Mike's, etc. Then, couple Joe as the guy who always sent Jim's messages, and you have valuable meta data on beginning to decode messages.
This was part of Gordon Welchman's work that revolutionised military signals intelligence: Previously, everyone concentrated on the message content, but Welchman is credited with being the first to realise that what is said in a message is only part of the information that can be extracted from it. The identity of the sender and recipient impart information, as does the schedule of transmissions, the transmission power, and the attitude of the sender: a good Morse listener can't just recognise a "fist", they can also hear how relaxed or stressed that sender is, just a you can tell how relaxed someone is by their voice.
So, if you recognise an operator in Hamburg's keying style and know he sends lazily-keyed confirmations to messages about fuel supplies every morning, usually to other operators in the Baltic, but suddenly he's responding to stations in Dover and Rotterdam as well and with more urgency than his usual lazy fist, then it suggests that there's something happening along the Channel that might be worth sending a spy-plane to look at. And you discovered this without having to decrypt a single message.
>The other type of personalization was the Morse code sending itself. (Being an old ham radio operator, I speak from experience.) Every Morse code operator has his, or her, own rhythm.
I can confirm this. Being an old military telegraphist I too have experience in this. Where a dot lasts 50 - 80 ms the variation is of the order of a few milliseconds, it is surprising how quickly you learn to recognise everyone on the net. I learned to recognise all my colleagues and no two operators ever sounded the same.
Adding to the above poster it should be noted that you had some counter measures when enemy intelligence was clued onto you: use the other hand. The "fist" for left and right hands are very different and would be confused for a different person.
There are tons of stories in the world of Morse code.
The other type of personalization was the Morse code sending itself.
Yes, but that was for the people listening to pick up. Most of those were ordinary citizens that had (or got) a suitable receiver, with motorcycle messengers collecting the messages that were copied down. They did get told, if not trained, to spot particular operators by their keying. And of course particular Wehrmacht and Kriegsmarine stations were listened to by army staff radio operators, with a quicker way to get interesting messages to the code breakers.
The transmitters used have their own personalisation.
The equipment would have their own attack and decay characteristics (rise time and fall time) which could be seen on an oscilloscope. Also overshoot and 'ringing' and ripple on the pulses.
I don't know if oscilloscopes were around during the war years but were used in the '60s.
I don't know if oscilloscopes were around during the war years but were used in the '60s.
They were essentially the basis for radar, to the point that initially radar was just displaying the scope trace for the echo from a (semi)fixed[0] antenna. Only later the rotating sweep came along.
They certainly weren't used widely for identifying enemy transmitters, if at all.
[0] The antennas could usually be rotated, but only slowly because of their size. More like getting them pointed in a particular direction and sort of tracking a target.
>They certainly weren't used widely for identifying enemy transmitters, if at all.
Was rather more low tech - from the operators PoV, they synchronised 2 different signals in a 'stereo' headset to get the range/bearing at the start of transcription. What sat behind that is presumably rather more complex than simple triangulation, but that's definitely what they did as my father was deaf in one ear and someone had to do this for him each time the source changed.
There was also the method of generating cribs which was known as "gardening".
BP would get the RAF to drop ("sow") mines into the sea at a specific location. Later, they would "reap" the benefits by looking for reports which contained the word for "mines" and specified the location.
I hadn't realised until recently that the Soviets tried to get cribs on an industrial scale in the 1940s. Guy Burgess was one of the Cambridge spies and at the time was working at the BBC. He lobbied to be given access to non-secret Foreign Office cables, in order for the BBC to be able to better report foreign news. The real reason the KGB wanted this info was to have the actual clear content of enciphered FCO cables, that they could then use as a crib so they could read everything in that cypher. Of course more important messages might be using a different code, but the more you can read of the other guy's messages the better.
At the Beeb he wasn't getting much info. Apart from making good contacts (he was the original producer of the Week in Westminster on Radio 4 - that's been going ever since) - so he was desperate for more. Sadly the Foreign Office gave him a job, before the Beeb got round to sacking him for being drunk too often.
>I hadn't realised until recently that the Soviets tried to get cribs on an industrial scale in the 1940s.
John Cairncross was the KGB's man at Bletchley - he passed a large number of decrypts to the Soviets and they some understanding of the technology and methodology at the very least thanks to him - he wasn't discovered and turned until the 50s by which time he was at MI6. Cairncross is reluctantly part of the official narrative now - although he's usually treated sympathetically and the scale of his treachery underplayed in the, mostly horribly inaccurate, dramatic accounts of the period.
Also important to remember that Soviets captured a lot of kit and expertise from the Germans - and most of the Bletchley Park Poles - 'Rejewski' notably - went back to Soviet Poland immediately after the war. With hindsight it's probably difficult to imagine, but there was actually hope things would be rosy under Stalin. Officially the story remains that their wartime roles were unknown to Soviets - though that's at odds with level of intelligence they had and the fact that Rejewski wrote one of the first detailed accounts of the work in the 1960s.
... the finer points of operating an extremely complex machine over 70 years ago
It's funny, you know, but I can. In fact, my earliest memories seem to be the clearest. She was 18 when she did this, and my 18 year old memories are still pretty clear (sometimes uncomfortably so). I used to repair Teletypes at university for some extra money, and I could still probably take one apart & put it back together, since I did 25 of them every summer (replacing bearings and re-lubricating them).
Since decades there are serious speculations about high-ranking spies in the OKW general staff. Several generals in the Eastern Front planned their own offensives, without interference from the General staff, often referred to as the "Spy Nest" by people like von Manstein. Some say Martin Bormann was a Russian spy. Maybe this enigma stuff is made up to create a smoke screen.
This kind of leakage is sort of detectable by smart people, they will notice when "by coincidence" the enemy seems to be on the right place at the right time each time something happens.
It is however unclear why German counter intelligence was so bad, the incredible losses in the U-boat war, was a clear sign something was off, since Oceans are big, and they seem to be spot on all the time.
You can read about Admiral Dönitz desperation in his memoirs, but they never thought their special Enigma machines could be cracked.
Also, getting the germans to believe the bristish navy could detect the radar installed in the submarines helped, as they were made to emerge blind.
But really, the Enigma cracking was top secret for decades, pretending to believe that such a highly detailed cracking was faked decades after those alleged spies needed protecting makes no sense.
pretending to believe that such a highly detailed cracking was faked decades after those alleged spies needed protecting makes no sense.
Three reasons.
Enigma machines were handed out to allies who weren't told that they were broken - so the UK/USA could read the secrets of 'friendly' countries for decades.
To keep the USSR underestimating the achievements of western cryptanalysis in the hope that they would be less careful/put less effort into advanced codes. Pointless wiht the number of KGB agents working for MI5
Possibly most important. To prevent the story that the Nazis only lost because of crypto becoming a political norm in Germany. If you lost because the other side 'cheated' then there is a justification to try again ( but this time with better OPSEC). Similar to the German belief that their army was superior in WWI but had been betrayed by traitors at home - so if they could only remove 'non-Germans' they would be victorious and so it was worth trying again....
naive,
German intelligence were seemingly often rubbish (though not always). They made some terrible errors. For example Von Paulus' plan to invade Russia called for the destruction of the 400 divisions of the Russian army West of Smolensk. Which they pretty much achieved. Unfortunately Russia had 600 divisions. And the remainder stopped them from taking Moscow.
By 42/43 Most of the planning staff of Army Group Centre (in front of Moscow) were in on various plots to assassinate Hitler. I think Von Stauffenberg was there for a bit, and he and various others shopped their plans around the army high command looking for supporters and a star general to be their figurehead. Nobody would take the job, but nobody ratted them out to the Gestapo. Who were totally unprepared. There must have been around 100 officers who know Von Stauffenberg was going to do it, which is huge for a conspiracy that doesn't leak. One bomb that was placed on Hitler's plane in Ukraine (in 43?) failed (due to cold I think) and the conspirators simply removed it after the flight with nobody being any the wiser.
Several german spies dropped by parachute or sub into England didn't speak fluent english. Which is just rubbish.
Canaris was aware of some of the plots to kill Hitler and several Abwehr officers were actively planning them. Being at work I don't have my copy of Joachim Fest's 'Plotting Hitler's Death' but Google is your friend - see wiki link - and note the 3 chiefs / ex chiefs of the German general staff in on it (Beck, Brauchitsch and Halder).
I think the German intelligence community suffered from groupthink. If Hitler didn't like an idea, then it was very hard to maintain it or prove it. And also of course, if Hitler did believe something then even if you could prove it to be wrong, it was still very hard to do so, or to act on that knowledge.
German intelligence were seemingly often rubbish (though not always). They made some terrible errors.
A particularly stunning bit of leading German intelligence, and with it the General Staff, by the nose has been Operation Mincemeat, IMO. At its centre was a corpse with fabricated documents including a letter by the vice chief of the Imperial General Staff to the British Commander in North Africa, detailing an invasion of continental Europe via Greece and the Southern Balkan, with a decoy attack on Sicily. As the German Abwehr after much scrutiny decided that yes, this person and the papers he carried were authentic, a fair bunch of personnel and material were moved from Italy to the Balkan. It took weeks before the Germans actually figured that the Sicily invasion was the real one.
German Intelligence did not just suffer from hubris, they also had the disadvantage that after the Battle of Britain they had way less possibilities to use aerial reconnaissance to corroborate info, as well as less human bodies doing the spying thing.
Operation mincemeat corpse was discovered by the Spanish and the information reported to the Nazi command.
Which was part of the ruse. Spain was technically neutral, although quite chummy with the Germans. The Mincemeat group figured that either the letters and other items themselves would pass German hands for copying and inspection before Spain handed them back to Britain, or the Spaniards would do that for them. Afterwards the letters were checked, and they had indeed be opened so that part of the operation could be verified to have worked. With Axis troops actually moving to the Balkan Churchill was then notified of "Mincemeat swallowed whole".
"Afterwards the letters were checked, and they had indeed be opened"
This bit was shown in "The man who never was".
Miles Malleson playing the boffin was given the envelope. "This has been in water...." snips a piece off, puts it in a test tube, adds water, gives it a shake, adds silver nitrate and gets a white precipitate "...seawater.". "But had it been opened?" (Dismissively) "Of course."
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>It is however unclear why German counter intelligence was so bad, the incredible losses in the U-boat war, was a clear sign something was off, since Oceans are big, and they seem to be spot on all the time.<
I'm old enough to remember that all the post-war documentories, for many years, didn't make that connection. In particular naval losses on both sides were always attributed to tactical changes. like "using convoys" It's now clear that the post-war picture we had of how the war was won, was completely wrong. It's sad that most of that early documentation will never be correctly re-written.
Some extremely clever chess players were taken to Washington DC, and tasked with analysing navel reports and predicting what the next enemy move would be. By some accounts they were quite accurate, but never really believed, because, well, they were just guessing. At this distance, I've never found out if they were just the cover story for the code-breaking reports, or if the chess was just the cover-story for people doing actual code-breaking work, or if the chess players were just a completely irrelevant parallel effort.
"Bletchley Park's code-breakers are credited by historians with shortening the war by two years."
This appears so often in BP stories that I'm beginning to think it's some kind of legal requirement.
It also ignores the fact that the Allies would have had nuclear weapons in 1945 regardless of the work done at BP. So BP may have saved Berlin from becoming an smoking hole in August of '45 but it's unlikely that it shortened the war by two years.
I think this is another US myth, as is the 2 year one. The 3 weapons detonated during the war exhausted the stocks of fissile material available, The next test wasn't until July 46 by which time Russia would have probably taken over most of Europe by then as, in all honesty, Russia's weapons production had reached such phenomenal levels that there was no stopping them.
And on the other-other hand.
With the Battle of the Atlantic lost and Britain with no food, fuel or weapons.
The Afrika Korp sweeping through Egypt, into the middle eastern oilfields and Rommel about to meet up with the Japanese in India - then all nuking Berlin would do is remove a layer of political interference
"All hail Ms. Bourne
She may not have had a fighting role but her contribution and those of other unsung heroes and heroines like her gave us the freedoms we enjoy today."
I fully agree with the sentiment, but - well, I read this article:
<https://www.theguardian.com/commentisfree/2018/sep/05/survived-warsaw-ghetto-wartime-lessons-extremism-europe>
"I survived the Warsaw ghetto. Here are the lessons I’d like to pass on"
by Stanisław Aronson. One point he made was this:
"Of course, many people did extraordinary things, but in most cases only because they were forced to by extreme circumstances, and even then, true heroes were very few and far between: I do not count myself among them."
I've lived a comfortable and extremely secure life in large part because of Ms Bourne and those of her generation who did their bit and I'm extremely grateful to all of them (including all four of my grandparents). But I do feel that the label "hero[ine]" is perhaps used a little too freely at times.
I've read "The last fighting Tommy" - the life of Harry Patch (now RIP), the last surviving veteran to have fought in the Great War trenches. He rejected the label of "hero" applied to himself on the grounds that he just went where he was told to go and did what he was told to do. Me? I think they're all heroes, all that lot.
The book "Enigma, the battle for the code" by Hugh Sebag-Montefiore ("Without for a moment belittling the world of Alan Turing and his team [...]") relates some often neglected aspects of the Second World War German naval code-breaking story, including the capture of code-books from German naval vessels. I expect the people involved in that would also deny that they acted "heroically" but it's not how I view their actions.
I suppose it all depends on your perspective. I once knew a bloke who'd worked on RDF back in the Second World War, and as far as he was concerned doing repairs to an aerial using a thermite powered soldering iron (so he said) while dangling about 200ft up in the air in high winds with minimal safety gear was just an ordinary day's work. The job had to be done, so you just got on and did it and at least no-one's shooting at you - that was his attitude.
There was an interesting story about the code breakers in, I think Albert Park, Victoria, Australia and they had broken some Japanese codes. For some unknown reason an American politician was given a tour of the facility and when he returned home he told his local newspaper about the great job "our American boys" were doing breaking the Jap codes. These codes were soon changed mush to the disgust and dismay of the code breakers who took three weeks to break the new codes. They wondered how many lives the big mouth pollie had cost with his stupid boasting.
This story was related by one of the Australian women who worked in the centre and were only allowed to finally talk about what they did during the war some time in the 1990s.
It was mentioned by someone further up about being careful what was responded to so the Germans didn't know their codes had been compromised. Let's not forget the people of Coventry as some of the victims who suffered to keep the broken codes unknown by the Germans.
Apparently the OSA still applies to some of the documents these people originally worked on (including the specifics of Bombe, etc) are still covered and rumor has it that GCHQ still holds copies of the original decrypts, containing information that may be relevant even now because it relates to people still living.
Last I checked, some of them *may* be released around 2024 but this is subject to official approval.
If the classified patents issue is anything to go by the "Fifty Year Rule" may be more like the "Whenever it becomes irrelevant due to technological advancement Rule" and some mathematical and fundamental physics discoveries may be affected by this. Never fear, most of them are related to obscure topics which probably have no relevance to everyday life.
I've run into the patents issue before, if you accidentally rediscover something that is classified you may or may not be asked (politely) to sign the OSA, hand over original documentation and sign an additional document stating under penalty of perjury that they are the only copies.
Just doing a search for certain terms of interest (tm) may get you visited by some folks or strange phone calls etc if reconstructed search history implies getting close to something you shouldn't.
https://apnews.com/23227e69754648c8b0e659f39151c0b1
WWII code breaker buried in Nebraska with UK military honors
OMAHA, Neb. (AP) — A 92-year-old woman has been buried in Nebraska with British military honors for a secret that she held for decades: her World War II service as a code breaker of German intelligence communications.
The Union Jack was draped over Jean Briggs Watters’ casket during her burial Monday, the Omaha World-Herald reported. Watters died Sept. 15.
The tribute honored Watters for her role decoding for a top-secret military program led by British mathematician Alan Turing, who was the subject of the 2014 Oscar-winning film “The Imitation Game .” Watters was among about 10,000 people, mostly women, who participated in the Allied effort to crack German communication codes throughout the war. ...
.... the 4-rotor bombe was built for the US Navy to handle messages encrypted the the four-rotor Enigma put into service by the German navy in 1942, in parallel with the British Mammoth. By the end of the war, 160 had been produced by the National Cash Register company in Dayton, Ohio. Most were located at the IS Navy Yard in Washington, DC.
It's worth echoing that operational security is *very* hard, and breaking the encryption is one of the last things to suspect. It's pretty much like burglars rarely bother with trying to pick a lock. It's easier to just look for an unlatched window or an unlocked door. Even if they get in using the door lock, it was probably using a key found in the unlocked car, under the mat, or copied by the valet.
The use of common words is actually an obvious back door.
The Short Weather Cipher (SWC) also did present similar vulnerabilities but the main loophole
was the lack of ability to encipher a letter as itself.
As any good codebreaker knows you have to be consistent: for example if I redesigned something of this era the first thing would be to replace the X as space with something more sensible like a relative reference *within* the enciphered text.
This would make it harder to read but ultimately a lot more secure.
Also useful: change the code sequencing so words are sometimes backwards, that should help a bit.
I developed a code not so long ago which uses references to sci-fi and (as yet) remains unbroken.
To decode it you'd need so much information that only an AI could break it.
No human could decode it unless they had memory in the petabytes *and* is essentially a cybernetic organism already.
Can actually be encoded using nothing more than (x) and (y) and a pen&paper.