 Now I've got PJ Evans from the National Museum of Computing He's going to be talking about reading Hitler's mind, Bletchley Park and the first computer. Please welcome PJ Evans Hello lovely EMF people. Thank you for coming along. We've got a double bill Bletchley Park double bill this afternoon because you got me talking about the first computer Which was invented at Bletchley Park and also following that you've got the wonderful Simon Singh With an operator's guide to enigma. So we're really going to geek out on cryptography this afternoon Before we get into it a little bit about myself 100 years ago. I used to write for this magazine About this device and I've been getting a lot of love for the ZX Spectrum. See people are applauding already Especially from great talks yesterday with Ben Heck and all the rest of it. So that's cool But these days I am a tour guide and volunteer at this place the National Museum of Computing Which is based at Bletchley Park. Now that if you don't already know is only about two and a half miles away from here So a lot of this is going to be me suggesting you go and pay a visit Because the people of Bletchley Park were very much like you people these were Makers back in the 1940s These were people who were put in an incredibly dangerous situation and had to think on their feet and never was it ever More true that necessity was the mother of invention They came up against the problem so difficult the only practical way to defeat it was with a computer The slight problem was the computer didn't exist yet. So what did they do? We do the sort of thing that you guys do they invented it So it's a great story and that's what I'd like to show you this afternoon Now if you come to the National Museum, you can come and see this computer. It's called Colossus It is the world's first digital programmable computer This is a rebuild of it fully functional But the story of how it came to be well, we have to go back to 1941 to start there And we start at Bletchley Park now. Is there anyone here who has not come across Bletchley Park before? Do I need to say anything about what Bletchley Park is and what happened there? Good right that's about two minutes off my talk time, which is going to make these guys very happy So Bletchley Park home of the co-breakers during the war most famously associated with the breaking of this device by people like Alan Turing and Gordon Welshman Now the enigma machine was in great use by the German military in fact the entire German infrastructure during the Second World War Its advantage was it is a very simple mechanical machine that encrypts very strongly It's very small and portable for the first time they could have secure radio communications right down to the front line Because of this small little device, but it does have its disadvantages You need six people to send an enigma message One to use the machine itself to encrypt the message type the message in watch the lights as they light up And what letter they correspond to Then you have someone who needs to write all that down And then you need someone who needs to transmit it by Morse code at the other end Three people have got to reverse that process ending with typing in ciphered message Into the enigma machine and seeing the plain text come back up That's six people who can introduce human error into the problem And they did a lot also it's not very suitable for very long messages It's about you don't want to send anything over about seventy and a half thousand characters and also very slow It's restricted by Morse code Which is a human operated thing? Now Hitler and his top generals needed something faster and more reliable for their top level Communications and they were interested in this technology teleprinter's Now teleprinter was a bit like the first text messaging system typewriter like device You could sit there type away happily and another teleprinter hundreds of miles away Tuned into it on shortwave radio will receive the signal it's broadcasting at output what you type on the paper And they can chat back to you as well Another advantage was that you could prepare punched tape And you could have pages and pages and pages of documentation that you need to send Encoded in this punch tape and feed it into the machine as all the broadcasts and receiving was automated It could go much faster about seven characters a second. In fact, it's such a robust technology It's still in use today in maritime applications. And if you come to the National Museum computer, you can hear live transmissions from Hamburg The punch tape because we're gonna get into this a little bit. That's what that's what it looked like It's actually very easy to learn to read it if I show you an overlay It's a five-bit code and each on that orientation each horizontal line represents one letter of the alphabet And it is a combination of five marks or spaces the holes and the gaps So there we've got J and you as an example just like the dots and dashes and Morse code But always in five so we refer to it as a five-bit code now the problem was That this was very fast very reliable But not encrypted so anyone listening in could just take the signal plug it into their own teleprinter because this system was an International standard and listen to what was being said that was no good So they built an attachment for it the most fiendish encryption system the German military ever had And this is a picture of one's only two left in the world that we know about please check your lofts if you've got one Let me know okay. I'll give you a 10 or 20 quid tops for it and This is actually this one here is actually the only one that works still the other ones too badly corroded Take note of the 12 rotors Across here or wheels as a sometimes referred to that comes into it later on What this device would do was take the paper tape coming out of the teleprinter machine It will be fed through this Automatically encrypted and then fed into a radio broadcast system At the other end that process would be reversed I'm just to make sure it was absolutely secure. It was it's capable of 15 billion billion different key settings So there's our new workflow Operator uses the teleprinter goes through the Lorenz machine the runs SSN 42 and into the radio equipment It's then broadcast and the process is reversed the upshot is you can stand there type away quite happily and The operator at the other end doesn't need to do anything else just sees the plain text German coming out But in between you know if you know the old Alice Bob and Eve Paradigm so even the middle only gets the encrypted message fast reliable Huge though if you had a mobile unit it took three trucks to move it around so it was only used For high-level networks. So what they did is they decided to build a communication network for the top military Now we don't exactly write to Bletchley Park and say oh and by the way we've set up a new network You might want to take a look at it. It's something new Here's how it all worked of course Bletchley Park had to discover it and they did What happened was that the Metropolitan Police started picking up a new signal and it sounded like this Now any of you listen to Morse code. No, that's not Morse code. It's going way too fast for Morse code We was actually nicknamed non Morse by Bletchley Park. We now I know it today is international teleprinter code And what they realized is that these codes are being sent out from Berlin using directional antennas and a big major network was being built up It got nicknamed fish at Bletchley Park because he does a little names and each spoke of the network was named after a different fish So we've got codfish What's your one turbot dace and then they forgot what fish were so they call it octopus squid And so on and so forth as his network was built up First job to do was to start monitoring these new signals So they set up a dedicated listing post known as a wireless intelligence station at Ivy farm in knockout in Kent It's still there. That's actually a very recent picture of it about 300 staff work there Mostly rends the women's Royal Naval Service and their job was to intercept these new signals and transcribe them I'll tell you princess reasons. I haven't got time to go into now Couldn't understand the signal so they actually had to painstakingly record them using a device called nundulator This is a piece of undulator slip and it's a visual representation of that radio signal So the high beeps are the peaks and the low beeps are the troughs So what's not obvious here that these are all in groups of five and it's a truth table. It's true or false So we've got for instance True true true true false. That's a five-bit code mark mark mark mark space So the renders would have to read that individually and then transcribe it back into the original punch tape form So it could be analyzed painstaking job a few months ago. I was giving a talk at the National Museum of Computing and I was walking along with a piece of this actual slip and Went past a nice little old lady and she started reading it out to me. She'd oh, yes, that's an A. That's a Z 70 years old on and she could still do it She worked at knockout When knockout had the signals they sent them up to this building f-block in Bletchley Park It's sadly no longer there because BT thought it would make a much better car park than a very historical building So that's what happened to it in the 1980s But the building just threw it there that you can see at the background through the arch That is now the National Museum of Computing. That's H block and you will actually go up that very same road F block was set up to analyze these signals But what they didn't realize then is it was about to become the world's first computer data center But we'll get to that in a bit so Messages are being captured. They're being set up to F block for analysis and they are getting nowhere With enigma the machine was commercially available before the wall broke out and one of the co-breakers Dilley Knox owned one The military version which was much stronger to use Were being captured by the poles they'd built replicas of it analyzed all the wiring and given all that information to Bletchley Park So a lot was known about enigma and that gave them a head start and getting into it this new thing that this new Cypher they knew nothing about it We didn't even know what the machine looked like so what it was called never mind how it worked and it stayed like that all through 1941 at the end of 1941 something remarkable happened a New branch of the network is being set up between Athens and Vienna One night two radio operators are testing out this link Using the teleprinter's and the chatting to each other on the keyboards They're not encrypting because they're not saying anything particularly important is just testing the equipment, but knockout is listening in anyway Suddenly one of them announces that he's about to test the secret writer Knockout get very interested He then does something no one's seen before he says here are your settings and sends these 12 letters Now any if you know about enigma, then you know that you've got to talk about rotors plugboard settings ring settings things like that 12 letters. This was something new He then sends around a 4,000 character message. He's not prepared it in advance. He types away at his teleprinter At the end of the transmission, which took quite a while Vienna radios back and says sorry old chap didn't get that could you send it again? I think he was annoyed Because he then went on to make two of the greatest mistakes in the history of cryptography mistake number one He said, okay, I'll send it again use the same settings again Now if he'd sent that exactly the same if he'd used a punch tape Let's you part could have been on the wiser But he didn't he made abbreviations all the way through about hundred characters shorter per second time round Now in cryptography terms if you get that it's called the depth of a message They'd never had a depth before for this new cipher. It was the first time they had the settings and two messages from the settings So they were able to compare them mathematically and that's exactly what this guy did Brigadier John Tiltman Arguably one of the greatest Co-breakers ever to work at Bletchley Park He was specializing in Japanese ciphers at the time But was brought over to f-block to work on this new one with this new information He spent about six weeks analyzing the two messages and a stroke of brilliance cracked it wide open He realized they were using something called a vernam or one-time pad cipher So I'm going to briefly explain how this worked The first column here is our message in this five-bit code form and what we've got here in our example is the letter M International teleprinter alphabet What this device was doing was generating a second series of patterns the same length as the message and pseudo random they had to be pseudo random and Then it would perform a little mathematical trick called X or on it now Just to explain what happens X all basically means if they've both got a mark then put a space if They're different put a mark if they both have a space So on the end with look at the first column there is a mark on the end There is not a mark on the first column therefore that scores true put a mark for the rest of them They're all the same It's smark mark space that one's mark mark space as well. So you say nothing That is your encryption process. We now have the letter T and that's the ciphertext that you send At the other end and identically set up Lorenz machine generates exactly the same key stream and reverses that process and you get your letter M back Now they have this information Two things needed to be worked out. Firstly How does it do that? How does it generate that stream? It can't be truly random. It must be pseudo random. How does it work? And secondly, how do you work out where it started? If that's a secular? Stream you've got to find out the starting point just like with enigma So here's how the break worked when Tiltman had this moment Here is some ciphertext from the first message And this is a ciphertext from the second transmission what Tiltman noted is that a few letters in here It changes So he quite rightly assumed that the first few letters of the message are going to be the same in both and Then he had a stroke a genius He figured that both these messages are a combination of the key stream and the plain text message added together using XOR If he adds both of them together using XOR The two key streams cancel each other out and what you're actually left with Is a new piece of text which is just a combination of the two plain text messages the key stream the encryption bit has gone What you need to do now is crib the message You need to come up with a words or phrase that you know is going to be in that message Thankfully the Germans were very helpful with this the German military very fastidious They always kept to doing the same thing following procedure over and over again Tiltman already knew that the first two words were definitely going to be some rock number message number so he thought well, okay if I take some rock number and Add that using XOR tonight It's back If I take that and I add that To my combined two messages It should remove that and then produce the other message So if I add that and I've got it right what should come out is another piece of plain text German So we did the first few letters I Got that Spruck nr nr like we short number to n o in the English language. He knew he broken it a Few hours of teasing the message out later. He had the first full break So now we knew how to break this message if they had the settings But it was still a long way to go firstly they had to work out how the machine itself worked That fell down to a man called built us anyone here heard of built us That's really gratifying to see it's great that his name is getting known because we were campaigning long and hard Because what this man did was incredible. He became obsessed with the problem of figuring out how this machine works how to reverse engineer it and He spent three months Working at Bletchley Park. He used to sleep at his desk a lot One of his co-workers thought he was actually wasting everyone's time because he just seemed to stand that and stare at the window for hours on end But he was wrong. He was thinking at the end of that period. He astonished his colleagues with this diagram It explains with 100% accuracy as it turns out Exactly how this mysterious machine worked. They've never even seen a picture of it All they've had to go on as those radio signals and now they know exactly how it works Those five bits that make up each letter were passing through two sets of five rotors The first set the K wheels always make a change to the letter and then all rotate and change the next letter in a different way the second five Only turn sometimes so they might make the same Procedure on a multitude of letters whether they turn or not is controlled by the two motor wheels at the bottom 12 wheels And if you remember there were 12 letters The historian Jack Copeland described this as the greatest intellectual feat of the second world war Also, the National Museum of Computing being completely biased completely agree What this allowed Bletchley Park to do was build their own version of this remarkable machine And they called it Tony the old name for tuna Now the Tony machines. This is a very rare photo of the actual real Tony machines at the time One of the frustrations of being a presenter talking about Bletchley Park is there just isn't that much You know, they weren't exactly running around with cameras There's very little evidence of this place even existed So I've got a better photo here and this is taken from our rebuild of a Tony machine at Bletchley Park It's fully operational and every day all day the tour guides people like myself will actually demonstrate it operating for you If it looks a bit like an old telephone exchange, it's because it's an old telephone exchange And the reason for that was simple They need an electronic device for speed and the best people electronics were the general post office who are currently building out the telephone Network so they took the requirements to them at the research center of Dollars Hill And that's what they came back with because that's what was in the parts bin These are rows here represent those 12 wheels that make up this machine the Lorenz and Once you knew your settings, you will plug up the machine And then the teleprinter in the corner if it all works You should be able to type on the teleprinter and what should come out on the page should be plain text German If you've got the settings and that was the problem The Athens and Vienna messages were highly irregular They did not normally send out the settings at all what they sent out was a number No one at bless you parking you are number represented and it was a in fact at the end of the war They found the operators code books were doing with open to the page number And there would be all your settings for your Lorenz machine of course. They didn't have that so they were stuck John tiltman had actually worked out a Way of breaking Lorenz. You needed three things a pencil a big pad of paper at about six to eight weeks per message Providing you didn't make any mistakes Which of course he did all the time So this was a problem the information obviously was stale They use different settings on every single message they sent and it was about 300 a day coming in at that point Six to eight weeks wasn't gonna work But that's how they did it to begin with because it was the only option they had The question was asked could we build machines to speed this up? You see tiltman also with our ensuring sale but come up with a algorithm and Have run if you run through all the permutations of the starting positions of the first five rotors of the machine using this algorithm You've got statistical information out correct analysis of this statistical information Which is very hard to say would result in Locating those first five wheel settings because of the way the second group of five worked only turning sometimes That actually turned out to be a gigantic Achilles heel for the machine And it could only you only needed about two to three hours to actually figure out the remaining seven settings But at the first five six to eight weeks They went to a man called Max Newman He was a bright chap. He taught this guy at university So he set up the new memory and The new memory was responsible for designing machines to help F block analyze these messages faster Their first attempt looked a bit like this it was nicknamed Heath Robinson by the operators and It was quite an incredible machine It basically sped up the counting that had to be done to run through this algorithm for use of relays The tape was pulled round by sprockets and passed a tape reader and the relays will cluster away happily producing this information It did speed things up. It actually brought the break time down to about two to three weeks Provided it didn't explode Which it did quite a lot They would often there's stories in the official reports of some of the workers going in and just seem clouds of smoke as yet Another relay has gone and also the sprocket system would wear the tape out quite rapidly as well So that would snap so it wasn't a great design, but it did show the way forward GPO is asked to consult on the project to see if they could make any improvements and this man took it on Anyone heard of Tommy flowers? Hey good a toy flowers head of switching at the GPO at Dollars Hill and He looked at it and said no no no no no Needs to be a lot bigger And these slow relays we need to replace them with something much faster. We need to replace them with valves Doesn't have to be anything fancy and these are just that's just a standard pentote valve there I see designed a machine that used 1500 valves He presented the design to Plexi Park who told him to get lost Why because they had radios and they had about two or three valves in them and they were a nightmare the valves failed all the time I'm a sheen with one thousand five hundred valves. It's insane And he said no what kills fouls is thermal shock. They do not like being switched on and off again So All we got to do is leave this machine running 24 hours and they said absolutely not But if you want to build it on your own on your own pocket go ahead. So we did a Dollars Hill still standing today at the research center now luxury flats Isn't everything luxury flats these days He designed and built his colossus mark one one thousand five hundred valves the results were incredible and Bletchley Park got interested Not only did they approve his mark two version with two thousand five hundred valves He also ordered another nine Only nine photographs exist of the original colossi and this is one of them But let's have a look at the machine in a little more detail if this is gonna behave Yes, there we go so you'll see some images are there So what we've got is an improved version of the Heath Robinson You have a bedstead there the tape on this is running at 30 miles an hour Reading at 5,000 characters a second uses tension to drive the tape around so it doesn't break And also you see there a light source reading in the message So the light goes through there through some lenses that blows it up into five photoelectric cells And you could not just nip down to Tandy or tires shows my age doesn't it? so mapplin I Buy five photoelectric cells They were actually considered the military top secret at the time all that gets read in time and time again into the machine The valves are actually generating the key stream of the Lorenz machine Applying that algorithm making decisions based on it, which is why it's a computer and then creating statistical data Now the reason they had to have that at all running around on that bedstead was because they had no memory Colossus has zero bytes of RAM They hadn't got that to that point yet. So it had to be read in time and time again. So that acted as its storage At the end of the run the teleprinter at the front here would spit out some statistical information One number above all the others would stand out to the code breaker And that would tell them what the first five rotor settings were because of that floor I mentioned earlier the remaining seven was only a few hours work away And in fact another machine called dragon speeded that up as well So let's review timings By hand six to eight weeks with a working non-fire exploding he from some run two to three weeks Colossus could finish its run in under three hours With this machine they started decrypting messages in bulk and what they found was that this network is being used by Hitler himself often signing the messages personally to give information to his generals in the field Now let's see park had a direct insight into what this man used the term advisedly was thinking So a quick timeline of what happened just to point out because I want to give some credit to the code breakers before Colossus here 1943 Battle of Kursk the first big Soviet victory of the Second World War and still to date the largest tank battle ever Part of the reason for that success is that a few days prior Gokko breakers had cracked the entire German battle plan by hand and They sent that information to the Soviets never telling them the source them 1943 the mark one goes live at Dollars Hill and In January 44 it moved to Bletchley Park. It starts breaking real keys in February on the 1st of June 1944 Colossus mark to the two and a half thousand valve version goes live at Bletchley Park Date right mink might ring a bell with you on the 5th of June a Piece of information is decrypted so important that Tommy flowers himself meets Eisenhower head of the American military at that time and the Allied forces To deliver it to a secret meeting is held He hands the information to Eisenhower Eisenhower doesn't say anything to anyone else in the room about this information Where it came from or what it said? What the information said? Was move your generals from Normandy to Calais signed Adolf Hitler Führer Operation fortitude had been a success operation fortitude was an audacious campaign to fool Adolf Hitler into believing we were going to go into Calais not Normandy So we would move his troops away and leave it poorly defended This included gigantic inflatable tanks Sounds crazy But if you imagine and we're now at 1944 The fields of Kent were covered in hundreds of these inflatable tanks and canvas spitfires a fictitious army The first American army was invented and pattern put in charge So of course the reconnaissance planes came over and saw them all massing in the perfect location to launch an assault on Calais When he read this information Eisenhower just put down the paper Looked at the other people in the room and said we go tomorrow 6th of June 1944 D-Day So I've only got a few minutes left. So quickly. What about the legacy of Colossus? We've seen how it played a vital role in the closing years of World War two, but what happened after that? Well all ten Colossi were destroyed Taken apart for spare parts and also to help protect their secrecy That's what GCHQ tell me to say it's not what happened Actually what happened was this the Russians came into the east of Germany at the end of war and they found enigma machines They had nothing of this level of sophistication and of course we'd not said all word to them about being able to read Lorenz messages They did exactly what Churchill wanted them to do. They didn't improve their own existing cypher technologies. They adopted Lorenz Two Colossi were taken here to GCHQ East Coast Which was the next state of evolution of Gleipzig Park and then later on down to Cheltenham Which of course are still there to this day and those two Colossi broke Russian Lorenz messages right through the Cold War to about 1965 What about the other people involved in the project? Well Tommy Flowers went back to a further ordinary life working at the post office Of course never spoke a word to anyone about what he was working on But suddenly a lot of the universities around here got very good at building computers in the late 1940s We had the Manchester baby and a remarkable machine who was head of that project. Oh, yeah, our friend max Newman Of course, they knew nothing about what he'd been up to And his colleague on shoring Well, he started building computers as well He built the pilot's ace with his team You never got to the end of the project, but you can go and see that machine in the science museum in London And in Cambridge the edsac got built Edsac currently being rebuilt at the National Museum of Computing. You know, do you see I keep getting the hints in yeah That will be going live it's actually been tested for the first time this weekend, but it'll be going live in 2015 Edsac project was funded by Leon's now they were the Starbucks of the day there was a Leon's tea shop on every corner in the 1940s 1950s and They had a massive problem with inventory and delivery and they were had enough foresight to think well Maybe these newfangled computers can help so they actually helped fund the edsac project and edsac became the prototype for the Leo mark one the world's first business Computer and from the Leo we're Leon for our answer something here and they set up a business Leo office systems the world's first commercial computer company Suddenly computers are broken out from military and academic purposes and before you knew it They're everywhere, but we can all trace it back The tommy flowers and his incredible machine So I've got a few seconds left. So we're gonna absolutely totally pitch this as hard as we can Some of the amazing things you can see you can see the which the world's oldest Original computer by about a decade that still operates. That's the original one still working away designed in 1949 Incredible, and it'll blow your mind if any of you are techies out there I think of I'm a pretty safe crowd for that. It doesn't work in binary. It works in decimal. Think about that. I Don't get it either but You can see lots of old computers and stuff and better still we're a hands-on place So we let you go and play on them We want people to be hands-on get on those computers even more you can become a volunteer And you can help restore them. We desperately need people to come and help It's like a playground of tech honestly, and you don't need to live nearby You can donate an hour a month or eight hours a day. It's completely up to you If you're interested, please come and see me after the talk and it's really really close if I haven't pointed out already In fact, there's you pick your favorite unit, but of course most importantly for you guys We do have perfectly acceptable coffee But wrong way there we go. All right. I better be quiet now do hang around for Simon sings presentation on enigma I'll have we got any time for any questions or are we are we looking a bit tight? Do come and find me if you do have any questions. Are we are we saying no we've got to get going? We're saying no Okay, but I made a question slide Okay, all right never mind amount of time But thank you very much all for coming in here in the talk and pleased to comment and support the National Museum of Computing