The Inner Workings of an Enigma Machine

[@WardyLion]

The Enigma machine, while relatively simple in a mechanical sense, is an ingenious invention.

[@garlandremingtoniii1338]

So is a 2.2 GPM Sink Faucet Aerator, Male and Female Dual Thread Aerator. A real work of art, and also so very very functional. Wa-La!!

[@jsn1970]

James Grime makes encryption so easy to understand with his lively presentations.

[@kastensok]

Love this! I have a report on Enigma, in high school. I had to combine two subjects Mathematics and Danish; for Math, I did as much explaining as I could, for Danish, I watched and interpreted the movie Enigma (characters, storyline, symbolism etc.). So when The Imitation Game was released, I was so happy and hopeful. I love the movie, but one thing I still didn't understand completely from the movie was Christopher. Now I do. Thank you.

[@freshgasflow]

I managed to buy an enigma machine rotor , and wanted to know how it works. This video explains it very well. Thank you.

[@KAYNAT1]

I love your enthusiasm! Your delivery is concise, clear and thoroughly enjoyable. Thank you for taking the time to explain this device. What a fascinating design!

[@nishatnahianrahman4014]

In my opinion,this is the simplest explaination of this whole messy machine..loved narrator's enthusiasm.

[@kaca2903]

But what's with the audience? The talk was great, matter nicely explained and James as enthusiastic as ever.

[@luisluiscunha]

Knowledge of History, perhaps...

[@VideosVonDennis]

Because it was a German tool.

[@kenmendoza6932]

He didnt even start by telling the history of the machine. If I was sitting there no clue on what your topic is going to be and you just start by talking about how it works, no history of what it was used for or who made it, Ill just go straight outta there.

[@oliverfasola19]

Ken Mendoza the topic of this was probably “how a enigma machine works” if you don’t know what one is then don’t attempt to figure out their inner workings

[@soberek]

Because none of them realize the mammoth size of the problem to be solved and even bigger size of the importance of braking that code.

[@Anmatgreen]

So basically, it works by confusing the hell out of everyone, sometimes even those using it.

[@Akinius]

Does anyone know what Enigma simulator he’s using? I really like the way it shows the wiring, but I can’t find it on line anywhere... Thanks!

[@vin4523]

I salute you Sir Allan Turing.

[@buildmotosykletist1987]

Why?

[@MrFischvogel]

Great talk! Resume keeping it simple :) Thanks and best wishes from the physics department of the Technical University of Berlin

[@scottfuller5194]

And if think the Enigma was complex....it was nothing compared to the German Lorenz code machine, a 12 rotor teletypewriter of the highest complexity of the four (4) different code encyphering machines that the Germans used in WWII, the Enigma was used at the lower "tactical" level by the German armed forces and most German government departments, railway service, labor corps, etc and the Lorenz was used by Hitler and his High Command as their "strategic" code encyphering machine.....to transmit orders and receive high level situation reports on those ordered operations.....! The Lorenz was an extremely complex system, far beyond the Enigma....!

[@ulrichkalber9039]

and the machine to attack this Code was called colossus. a beast of a machine. a working one is in the national Computer Museum in Bletchley park(it is a separate Museum from the actual Bletchley park). one of the tubes has a production date of 1943, and still works.

[@michaelbuckwash2412]

Wait. Colossus solved or “broke” Lorenz?!

[@martinluka5917]

Does anyone know where I can find the Enigma Emulator (I know there are others, but I am interested in this one) from the video at 6:30 ?

[@USER-jo7yz]

The best simple explanation about the machine.

[@bayuidhamfathurachman1276]

Come here after watching The Imitation Game movie ..

[@robingergolla9445]

haha, same

[@NoseyNick]

Bayu Idham Fathurachman Cool, so can you spot the "deliberate mistakes" in the movie now? :-D

[@grumbler1]

Bayu Idham Fathurachman same) finished watching an hour ago

[@AlessandroCarpentiero]

Same :D I had no idea about what Turing did about it!!

[@dasboot5903]

@@AlessandroCarpentiero >>> kzbin.info/www/bejne/maG1mY2Xht2hntk

[@coltino99]

How is the last column different from the middle one? If only one covers starting position, what’s the other cover?

[@batchrocketproject4720]

Agreed. Regardless of labels, each rotor only has 26 positions so there's a bit of duplication there.

[@paulneimoyer3201]

If you type an "A" for example, It will NEVER be repeated in the code. There is the flaw. An "A" will never be an "A".

[@rajeshsharmajaipur]

That's the first lead Allan Turing figured out.

[@DivyanshMMMUT]

@@rajeshsharmajaipur That's " Alan Turing "

[@rajeshsharmajaipur]

@@DivyanshMMMUT Ok

[@garlandremingtoniii1338]

@@DivyanshMMMUT That is, Alan, Luring.

[@DivyanshMMMUT]

@@garlandremingtoniii1338 ok

[@burtgummer463]

I found one at a goodwill thrift store back in the 80's Was mislabeled as an old typewriter. Thanks!

[@StandingSidewayz]

Are you being serious? If so, I've gotta hear this story.

[@zjones9876]

That would be amazing

[@Emtbtoday]

He was actually the best on e I've heard and understood from an enigma explanation 👏

[@BFree-ge6ms]

One of the Weasley twins when they're muggles.

[@cessposter]

Weasly's Mechanical Wheezes

[@ellenruth5238]

HAHAHHAH Exactly

[@KM6VV]

Forgot to say, Great video! I wonder if one could write a program for a microprocessor to encode/decode similarly.

[@crazycrab8578]

there are now a few programs on internet that do that , I then copy code then past it into my e-mails :)

[@phamapollo3175]

So if I understand it well, Enigma is a coding-decoding machine that can encrypt its own setting instruction, then decrypt it, with many many possibilities in each stage??

[@vister6757]

Plug board makes the combination more complex.

[@malgorzatacicholaz4485]

British in fact did not solve the enigma. It was handed over to them by the Poles. In fact, the "Enigma code was first broken by the Poles, under the leadership of mathematician Marian Rejewski, in the early 1930s. In 1939, with the growing likelihood of a German invasion, the Poles turned their information over to the British, who set up a secret code-breaking group known as Ultra, under mathematician Alan M". British themselves admitted in early 2000 that it would be impossible for British to solve enigma without Polish contribution ( they didn't go as far as telling that Poles did it, but we know otherwise). Movies are one thing; historical facts are the other. Since Poles were trapped behind the Iron Curtain, the British took all the credit for the enigma. The story of Marian Rejewski and his group of mathematicians is really fascinating, much more than a Bletchley Park story, in my opinion, because it shows the incredible dedication of a few men to solve the puzzle that lasted many years. If the movie was done to show real historical facts, I think everyone would be sitting at the edge of their chairs. I think you might be inspired reading the story of Marian Rejewski, if you have time....

[@andyj2106]

The Polish mathematicians were the first to break Enigma, financed by the French secret service. A German embassy official accidentally put Enigma rotors into the Polish postal system and between that point and realisation and retrieval, the Polish secret service were able to unwrap the parcel, note the wiring and then repackage them. They used this information to devise a process for breaking the daily settings. This was early on in the 1930s and it was a brilliant achievement. By the time war broke out the Germans had changed the machine and operating protocol such that the Polish approach no longer worked and the British then had to build on it to create a new attack vector. It's true the British didn't believe the Poles could have done it (snobbery on the part of British mathematicians) and were astounded when the Poles handed their work over. It's hard to say whether the British would have succeeded without the work done by the Poles but at the very least it can be stated that there is no way they would have done so by April 1940 when the Bombe started coming into operation. You're right that their story is interesting especially as they spent time working in Vichy France under the German's noses!

[@sriramchandramouli394]

While sending the message, prefixed by the ground setting for example ABCABC (repeated twice) the method is to code it using the same enigma machine and send the ciphertext. How will the receiver know to decode that ciphertext as ABCABC to use that as the ground setting for the rest of the message? I thought you need to know the ground setting before to decode anything. Please clarify !

[@Gigano]

+Sriram Chandramouli As far as I understood, you'd use the ground setting from the keysheet to decode the first six letters of an incoming message to get the encoded ground state. Using that setting you then decode the rest of the message.

[@bluedivide1]

The prefix message code is noted on the daily setting and sent before setting the sending machine to the prefix for the message so both machines can code/decode the prefix on the same/daily setting and code/decode the message on the prefix setting. They soon altered this start method to a non repeat start code.

[@lisaavvento9065]

What shocks me is I can answer that question, lol.

[@rustycherkas8229]

Sender: 1. configure device including setting-up rotors exactly according to daily schedule. 2. freely choose any three letters, then double the string (like "catcat" or "dogdog" or "sexsex" or "mnomno"). 3. type chosen three letters (twice) on Enigma keyboard and record the resulting 6 encoded letters as a "prefix" (perhaps "qwdfvb"). 4. ignoring the daily rotor setting configuration, (re-)adjust your machine's rotors to match your chosen three letters (eg: "cat"). 5. encrypt 'payload' plaintext appending output to the 'prefix' and transmit entire message. (If payload was "Hello", transmission would be 6 + 5 characters.) Receiver: 1. configure device including setting-up rotors exactly according to daily schedule. 2: record incoming morse code of what appears to be a gibberish message. 3. type initial 6 letters on Enigma keyboard (perhaps "qwdfvb") and record decode ("catcat"). (Repetition for quality control, but repetition created weakness.) 4. (re-)adjust rotors to match those three letters ("cat") - the actual rotor positions used by the sender from the start of this particular 'payload'. 5. decrypt payload (characters 7, 8, 9, ...) with your machine now being configured exactly the same as the sender's machine for this particular message.

[@robertcuminale1212]

Very similar to the rotary line switch on a Step by Step or Strowger Telephone Central Office. The switch has hundreds of contacts wired in a sequence so that the switches are used in a predictable order so that the first line finders do not wear out more than the rest at the end of the bank of switches. Instead of the rotary switches to change the sequence a relay matrix is used to set up a pattern of usage. ie: 1-5, 1-5, 6-10, 6-10, 1-10, 1-10 and repeat. This central office came to market in the 1920s.

[@jimw83296]

well, color me impressed!........in 1940, and nary a computer on the entire planet, and yet this!!.....so simple, yet so many possibilities!!!.....genius.

[@casedistorted]

ooo this makes it way easier to understand how the Enigma machine worked after watching that movie. The Enigma always fascinated me after watching U-571 as a kid in theaters when it came out.

[@stevenbennett3805]

The movie U571 was complete rubbish. It was a British destroyer that captured a German U Boat, took the crew prisoner, secured a 4 rotor Kreigsmarine Enigma machine with a complete set of rotors and code books and charts. The Captain of the U Boat was killed while attempting to scuttle the U Boat and the crew was taken to England, imprisoned in completly segregated from other prisoners and held in isolation and allowed no mail or Red Cross contact. This led the German high command to believe the U Boat had been sunk with all hands lost and the code still intact. After that, BP was able to decipher all the German messages and U Boats began sinking at an unprecedented rate. Doesn't make for a very interesting movie but that's what happened. Never rely on Hollywood to portray historical events accurately.

[@wolfvictor]

That was the best explanation I could find, thanks!!!

[@asd36f]

The Powerhouse Museum in Sydney has an Enigma machine, and 20 odd years I was able to visit the storage area and have a closer look at it - as a WW2 buff, it was a great thrill!

[@protectchildrenatallcosts2652]

Good. Would you like to have one or you prefer a new i-Phone? :)

[@scottfuller5194]

The "keys" are in the rotor wiring.....the daily settings and the actual cypher/code transmitted, thus the Enigma and the Lorenz are only the electro-mechanical encyphering and then deciphering "mechanism.....and by the way, Canada has 14 enigmas and 2 Lorenz NOT the 2 enigma that is stated here..... This is a valid descriptive narrative, less a few omitted facts.....

[@Gytax0]

James Grime for the win!

[@bigbob1699]

There is one on display next to the U 505 in Il.

[@simonjrobinson]

So how did the sender communicate his personal 3 letter message key? Is it a case of: 1) The sender setting up his enigma machine rotors according to the ground setting for that day (e.g. XYZ). 2) Choosing his 3 random letter rotor settings for his message key (e.g. ABC). 3) Typing these 3 letters (twice) at the start of the message. 4) And then changing his own enigma rotors to his own made up setting (ABC) before typing the main body of the message. ?

[@Pille1842]

You got it exactly right.

[@MrKen-wy5dk]

Watch the video again. It's clearly explained.

[@stevem9529]

Simon R by the end of the war, these machines had up to 8 rotors as well.

[@beatbeast747]

you clearly didn't watch the entire video

[@ronschwartz5565]

But could it sent emojis?

[@martakoszmider3989]

Oml

[@sweetsunnydaygirl]

+Ron Schwartz Truly laughed out loud, thank you:) I'm absolutely sure and positive that the machine would suddenly and inexplicably fall apart, rotors spinning, keys flying off the keyboards.... in its inept attempt to decode and descramble the innumerable nuances of human emotions farcically conveyed through emojis:)

[@egeinf]

In fact, the emoji "X" was sometimes used to reduce ambiguity (since there were no spaces).

[@beatbeast747]

yes, since emoji can be repsented through characters. :)

[@costa_kaplan3784]

XD

[@ruantristancarlinsky3851]

We have to code this for my Computer science class, this helped a lot

[@lordisitmine1]

Brilliantly explained, a delightful video, thanks !

[@christiancastro3501]

4:22 what happened there? What are the chances of the same focus rising?

[@djmarkalmond]

Did anyone ever find out which Enigma Emulator software he used in this presentation? Searched the web, found many others but none match this version? Any Ideas?

[@Lauracharland]

+djmarkalmond users.telenet.be/d.rijmenants/en/enigmasim.htm

[@Music20100608Love]

This is similar, but not the exact one. I was also seeking for the Emulator he uses for a long time, but did not succeed.

[@stevedevries2891]

I now know more than I ever thought I would about the Enigma machine, and I don't know what to do with this knowledge...

[@normanedwards7220]

Only last night I watched the film "enigma " it was about the code breakers at Bletchley Park, as a relatively normal human being I could understand most of what was going on , but , I was astounded by the intelligence of those people who cracked the codes ,

[@claycc79]

The Brits were trying to decipher the engima, why do you have to deal with trying to decipher the roters and all the alphanumeric conversions. The plugboard pins are a 1 to 1 conversion, if you just look at the plugboard conversation which is at the end of the chain, would it not solve the whole problem of trying to deciphering the enigma?

[@vishalgoel6690]

I cannot find this particular simulator of Enigma used in this video. Can anybody give me the link? This simulator shows the inner wirings as well which is not there in other simulators available on internet.

[@alfonsoantonromero932]

Good video. Who was the greatest polymath and why Allan Turing or John von Neumann? Both great mathematicians, forerunners of computer science, logicians, with fundamental importance the last one in economics ...

[@weirdsciencetv4999]

Do these simulations properly handle double stepping

[@frederickbowdler8169]

Does the key A have a switch that excludes bulb A from lighting up or can someone explain how A never shows bulb A or is that just a very rare event?

[@andyj2106]

Old question but you might get a notification! Keep two things in mind: (1) the machine is electro-mechanical so the electric signal from the battery through encryption path to the lamp is conducted along wires and contacts; (2) the signal path obviously can't travel "up" one wire and "down" the same wire as electricity doesn't work like that, it only moves in one direction. The Rotors rotate, as you saw, so the signal path is conducted across contacts at those points but you can envisage the encryption path as one long wire. Each Rotor has 26 contacts on its right side and 26 on its left side and these contacts are wired together on a one-to-one basis, i.e. a contact on the right side is wired to a contact on the left side and none of these contacts have multiple connections (i.e. a left side contact cannot be connected to two or three right side contacts) The Reflector has just 26 right side contacts, with each contact wired to only one other contact (so 13 wires altogether) The Input Wheel has 26 contacts on its left side and there are wires coming in from the Plugboard to each contact on a one-to-one basis, i.e. there is no contact wired to more than one plugboard letter. These 26 contacts can be deemed a letter of the alphabet. Note that the Input Wheel is not cross-connected so if there is a wire from, say, Plugboard letter Q to the Input Wheel it is wired to contact Q on the Input Wheel. The Plugboard has 26 letters that can be cross wired - e.g. letter A could be wired to letter Q or letter C could be wired to letter F; it is not possible to wire more than one letter to another letter, e.g. it is not possible to wire letter A to letter Q and letter C to letter Q. In operation, only 10 letters were actually cross connected in this way. the ones that aren't connected to another letter are internally connected to themselves. So, the encryption path created when a key is pressed is: Key -> plugboard in -> plugboard out -> input wheel -> rotor position 1 (RS to LS) -> rotor position 2 (RS to LS) -> rotor position 3 (RS to LS)-> reflector in -> reflector out -> rotor position 3 (LS to RS) -> rotor position 2 (LS to RS)-> rotor position 1 (LS to RS) -> input wheel -> plugboard in -> plugboard out -> lamp. The more confusing bit of the above is the plugboard in/out. What I mean here is that the signal enters as one letter, is cross-wired to another letter and then exits the plugboard (hence plugboard in and plugboard out). If there is no cross wire for a letter the input letter and output letter are the same of course. Hopefully by considering the above encryption path you can see it is physically impossible for a path to be created that links a keyboard letter to a lamp of the same letter as it would require that letter to be connected to itself in the encryption path - it would be helpful to pause the video where it shows the wiring path. Take a rather contrived example of pressing key A. Signal leaves key A and enters plugboard at letter A. It is not cross connected so it leaves the plugboard as letter A and enters the Input Wheel. The Input Wheel wiring is straight through so it leaves the Input Wheel as letter A and then enters Rotor 1 at some letter but lets say coincidentally letter A (remember the rotors move so it could be any letter). It then travels to the other side of the Rotor and lets just say that internally the rotor has wired the RS contact letter A to the LS contact letter A (some letters were straight-through connected in some rotors!) so it leaves as letter A and enters Rotor 2 at some letter. For the sake of the example I'm going to say that Rotor 2 and Rotor 3 letter A are straight through wired: thus, it crosses Rotor 2 and leaves as Letter A, enters Rotor 3 as letter A and then leaves Rotor 3 as letter A. It then enters the Reflector as letter A. Up to this point the letter has stayed the same purely because I've stated that the internal wiring of the three chosen rotors were straight-through wired. This internal wiring never changes of course but the actual number of contacts that were straight through wired like this is, I think but I can't readily remember, one pair of contacts on each physical rotor at most so the scenario is highly unlikely but it helps me explain why a letter cannot encrypt to itself. So within the Reflector letter A is cross wired to letter Q (all contacts are cross wired in the reflector). It leaves as letter Q (and I hope you can see it can never leave as the same letter that entered the Reflector) and enters the left side of Rotor 3 at some letter - it cannot be letter A though because that is already in use in the signal path and the left side contact letter A is wired to right side contact letter A. Thus whatever Rotor 3's letter LS Q is wired to, it also cannot be to Rotor 3's RS letter A. I hope you can envisage that the same occurs as it passes through Rotor 2 and rotor 1. Let's say it emerges from Rotor 1 as letter Z. So the signal enters the Input Wheel again as letter Z and that is straight wired to the plugboard as letter Z. Now letter Z might be cross connected to another letter in the plugboard but it cannot be to letter A as that IS NOT connected to anything as stated at the start of the example. Let's say Z is cross connected to letter H, so it exits the plugboard as an H which is wired to the bulb under the letter H on the lamp board. I hope that rather long-winded explanation helps!

[@ChannelReuploads9451]

Naval Enigma's were supplied with up to 8 rotors at one point, but only 3 rotors used at any one point. in 1942 there were 4 Rotor Enigma's being sent out, which in operation, the 4th rotor was Beta, or Gamma, and did not rotate like the first 3, but was still able to be set to one of the 26 combinations. The Monthly code sheets used what is known as 'One time pad', so each code at the end of the day, was discarded, and moved to the next. As already said, One Time Pads are great, but regular distribution of new pads was a logistical nightmare.

[@samspencer582]

The best thing ever made. An amazing machine.

[@lutzschubert7407]

The russian F-125 is even better!!

[@advocacyofthedevil3621]

Starting at 10:20 the speaker makes either an error in his calculations or he just read the number wrong for the rotor combinations: 26x26x26= 17576. Not 1576 as he stated. Even his display projection reads 17576. A small mistake, but one that could have changed the outcome of that war.

[@potterx98]

Haha yeah I noticed that. Just misread it, I think. 17576 is the right number.

[@anticeon]

Advocacy Of The Devil damn... you iluminaty i bet you have core i7 processor machine in 1940s.

[@protectchildrenatallcosts2652]

11:36 He said the correct figure.

[@leecambsuk2871]

Watched this as currently reading Hut 6 by Gordon Welchman. Would have liked to have seen a removed rotor to get a better understanding of it but overall a good supplement to the paperback I am reading.

[@tyfon4429]

What is it worth ? With five rotors for the submarine forces .⚠️ all fully original, from first hand . All funtional. Including the original case. SERIOUS QUESTION.

[@miladirani4313]

In first vision is very simple with few component inside (keyboard with wire and 3 gears) but i geniusly idea, i love this machine

[@rfdrivetesting2541]

which cipher does it use

[@mahantalok]

when he sent 'HI" and later decoded it he turned the rotor position 2 alphabets back so that TW became HI. but when the reciever recieves the message how would he know 2 turn the rotor back 2 places? is it on the numer of alphabets sent?

[@James-zs3vm]

He only had to move the rotors back twice so they would be set to his original setting (the setting had changed because when he pressed the keyboard twice the rotors moved), the receiver would already know the original setting and thus wouldn't have needed to change back

[@daniellower72]

The code books had a lot actually 1. Which of the rotors to use in what order. I, II, III. Five rotors in total. 2. The ring settings of the rotors when they turned over. S, D,Y. 3. The starting position of the rotors YYY say. 4. The plug board wirings where letters are swapped. T->B Set all that up and you can start encoding and decoding. Naval enigmas had something else to different kind of reflectors . You can get an idea by playing here. www.lysator.liu.se/~koma/turingbombe/bombe.html. Click the left button to open the box. Click shift to rotate the ring settings on the wheels.

[@Fredricful]

Enn vist jeg koder med apsolutt alle språk i verden og alfabet va ser da?

[@samueljackson6188]

what about numbers? how was that done?

[@Fredricful]

Kann jeg kode med det china alfabet va ser da?

[@bznbrian]

Wish I could find the emulator he uses at 5:20

[@binarybox.binarybox]

users.telenet.be/d.rijmenants/en/enigmasim.htm

[@lamyaa1594]

what is the name of the emulator?

[@Gardien48]

Good work! Where I found something how Turing cracked the code?

[@NoseyNick]

Martin Gardien en.wikipedia.org/wiki/Bombe is not the whole story, but probably a great place to start. It's the machine shown in the movie, though the movie deliberately skipped the fun-but-complicated stuff, and made a few rather surreal misrepresentations.

[@scottfuller5194]

Turing NEVER "cracked the code".......his work was focused on the Enigma MACHINE.....the encryption device......he worked to apply mathematics to work out the complexity of the MACHINE and once he (and several others) accomplished that......he applied his earlier theory that it would take yet another machine to "read" that encryption MACHINE....then he incorporated the Polish solution of their "bomba" (a series of polish enigma replicas wired together) to mathematically work out how his "bombe" could/would/should scrunch down to a workable level the astronomically complex number of possible permutations (combinations of numbers), to simplify the electrical mechanical process to rapidly "break down" the encryption reversing the process to arrive at the original plain text (in German) of the message, then translating that German text into readable English (bearing in mind the German use of quite a high number of military lexicon).....then sending, by hand-carried motorcycle courier, the plain English text to one or more of the British military services operational headquarters for their tactical and/or strategic use......and/or deception planning....soon after their success, the British would send more rapidly and most securely, that English version of the German plain text message to that military services' operational command using a one-time-pad (single use only) British code, encyphered on the British model/version of the enigma, the TypeX cypher machine (had more than six rotors and a three set encryption capability.....).

[@christianpatriot7439]

What did the plug board actually do to the machine's internal circuitry?

[@SlickyPants]

The plug board swapped pairs of letters. At 6:05 in the video, his Enigma simulator has the plug board settings: A-B, C-D, E-F, G-H, I-J, K-L, M-N, O-P, Q-R, S-T. In this example, typing in 'G' would first swap with the letter 'H' before entering the rotors. After hitting the reflector and making its way back it will first go through the plug board before illuminating one of the lamps. In the video, this came back through the rotors as an 'I' but then went through the plug board and was swapped with 'J' before lighting up "J' on the lamp board. The plug board could be used to swap any letter pairs, not just adjacent pairs of letters like in the example in the video. Leaving the plug board empty would not swap any letters and you could have up to 13 pairs of letters if you wanted. To summarize, each letter typed goes: keyboard > plug board > 1st rotor > 2nd rotor > 3rd rotor > reflector > 3rd rotor > 2nd rotor > 1st rotor > plug board > lamp board. The earliest versions of Enigma were marketed commercially without a plug board which was later added to military Enigmas to increase the number of starting configurations making it more difficult to crack.

[@axlslak]

I am fascinated by this. And I think some light has been shed on how Alan cracked it. Well, no by himself. The polish cryptologists too. And everyone else. But what fascinates me is what we take for granted. Meaning, the cap, the cap that is the same on every enigma machine. Little is said about that. I am sure there's a complete schematic of an enigma machine somewhere on the internet, but I would like to point out that the END part after the rotors, also scrambled letters around but was the same thing on all the machines. it is basically a constant. Without this particular knowledge you wouldn't be able to break the machine. And second... the rotors themselves. There's mention of 5 types. The ways wires connect from face 1 to face 2, is extremely important. And relevant. Without having the rotors, Turing wouldn't have been able to make simulations to find the other settings. Which leaves (as far as I am concerned) one question. Should we talk about the decisions that went into making that end-cap (dont know how to call it) and the way the 5 rotors are designed? First of all, how does the end cap differ from the 5 other rotors (other than its static) and just how many other rotors we could have? and how come in all this complexity, you know for a fact that A never ever equals A. Seems to me sometime A can equal A. It has 0 relevance, but that's a false statement that you hear about this machine. That a letter can never be encrypted as the same letter. Unless I'm missing something, it is possible one letter to be the same latter encrypted and decrypted. Still an amazing simple idea, without a cpu. Just a mechanical contraption that still can give a headache to a modern computer. Its not easy to crack these things. Even if you know how they work.

[@andyj2106]

I know this is an old question, but you never know you may get a notification. It is absolutely the case that with an Enigma machine a letter cannot encrypt to itself, the wiring physically doesn't allow for it - you can get some hint of it by pausing the video where the wiring path through the rotors is being shown. You are right when you say that without having knowledge of how the rotors, reflector and input wheel were wired then it is unlikely (maybe not impossible) that Enigma could have been broken - this wiring was known at the start of the war because of the intercepts the Polish had done. Indeed, when the German Naval Command introduced a fourth wheel into Enigma for their submarines, Bletchley Park could not break those messages until that fourth wheel was captured. During the war there were 5 rotors of which 3 were chose (8 for the German submarines, 4 chosen, from 1942) and 10 pairs of letters were cross connected on the plugboard giving over 15 quintillion combinations. Unfortunately for the Germans the fact that out of those over 15 quintillion combinations there were 26 that couldn't occur allowed the Poles and then the British to break encrypted messages on a daily basis. Thus it has 100% relevance to decryption. Although the reflector (and input wheel which didn't scramble but could have if they wanted) are fixed constants on every Enigma it didn't really matter as long as its wiring was known (which it was of course.) The fatal flaw that allowed the encrypted messages to be read were those 26 combinations that couldn't occur; allowing operators to swap the reflector wouldn't have altered that position. Actually, the Germans did try that at one point but it hopelessly complicated the whole operation of the networks so they stopped it pretty quickly. Incidentally, the British cypher machine during the war was TypeX and was a similar rotor based machine. However it didn't have the flaw of Enigma and letters could encrypt to themselves. I don't believe the Germans broke TypeX traffic, although they did break plenty of other allied encryption mechanisms.

[@axlslak]

@@andyj2106 Thank you :)

[@Fredricful]

Enn om televerke snapper opp alt dere jør va ser da og koder med det dere alle skriver og spiller på Internett va ser da?

[@jaymanu12345]

I notice the rotors are turning AS you press a key. I would expect them to turn on a key release to change the code for the next keypress. I guess that means we are always one position ahead, the initial setup being actually never used. clever.

[@ddelfao]

jaymanu12345 I don't understand what you mean by being one position ahead. Could you please explain to me? :) Thank you.

[@jaymanu12345]

ddelfao say you position the rotors in position 1 for start. Then press a letter. the rotors will turn to position 2, and then the resulting letter will light up. It will light up according to position 2. Position 1 is never used. Though i'm no expert, only guessing from what I see here, please correct me if that's wrong.

[@andyjg48]

fantastic lecture . you make it learnable ... if thats a word.. whats your name?

[@NoseyNick]

andy glover See where it says "Mathematician and cryptography expert Dr. James Grime" ? ;-)

[@rohitkumar-wx2uo]

Preconditions to understand the genius of inventor- 1. U hv seen d movie The Imitation Game 2. U r a maths lover 3. U know at least permutation combination. 4. U must have someone like this narrator in d video to explain things.

[@rfdrivetesting2541]

is it require KEY

[@martinh9099]

Enigma must have worked to some extent as Hitler never had his credit card scammed

[@Lauracharland]

I'm a bit confused. How can the receiver decode the ABCABC?

[@Carl-vm8ej]

+Laura Charland I think it is with the ground starting position written on the big piece of paper for each day of the month!

[@Lauracharland]

+Carl Hewett Thank you!!

[@mwamiral]

+Carl Hewett but then, how would you prevent someone that found an enigma machine and a book of starting positions to decode everything?

[@Carl-vm8ej]

Nothing! That's why the books were printed using special ink that would disappear when in contact with water. This would allow the Germans to quickly destroy these documents if they were at risk. That's what Wikipedia says, anyway.

[@bluedivide1]

+Laura Charland - The ABCABC is coded on the operators daily setting before moving the rotors to ABC not after, likewise the receiver decodes back to ABCABC on the daily setting to know where to move the rotors for the message.

[@eat_things]

What an amazing dude. Love this guy.

[@ct6502c]

sammyich I just watched a couple of videos with him and yeah I agree he's an awesome speaker. I really don't understand why the audience looks so brain dead here.

[@christianpatriot7439]

I've never seen it explained anywhere, but am I right in thinking that all possible rotors had 26 numbers, but each individual rotor had its own unique wiring so each rotor was different from all other rotors?

[@Inkling777]

Right! The Germans were suspicious enough that they made changes over time to improve the system. I believe the German army adopted five rotors, any three of which could be used. The German navy was even more aggressive, going to a four-rotor system, which gave the Brits a lot of trouble when it came out. Fortunately, the Germans didn't notice how badly that hurt British intelligence. There was another factor that's rarely mentioned. Much of this communication was tactical, meant only for someone a short distance away. To pick it up from hundreds of miles away the British used highly directional rhombic antennas, each wire leg hundreds of feet long, and installed them on 100-foot-high poles. If German aerial intelligence had spotted those antennas, they might have asked why the Brits were going to so much trouble to intercept communications if they could not decrypt them. en.wikipedia.org/wiki/Rhombic_antenna

[@christianpatriot7439]

@@Inkling777 The German navy went to 5 rotors once the Germans realized that they were losing U-boats to Allied attacks, but I think the army always used 3. The Lorenz Machine that was used between Hitler and the army high command used 12 rotors.

[@kylecho2912]

it's a triple rotor with no military marking so I believe its a commercial version

[@YellowSubmarine9628]

+Kyle Cho Each is £85,250

[@damanofdreams]

+Kyle Cho Military, specifically Luftwaffe and Wermacht versions that were used for "the most secure of transmissions" had 5 rotors

[@kylecho2912]

I remember seeing a photo with Heinz Guderian in his command vehicle one of his staff was operating a triple-rotor enigma

[@MCDreng]

Commericial Enigmas didn't have a plugboard on the front.

[@gregoryhoward89]

'There's no pattern to this' Oh yes there is!

[@JacksonPM23]

Holy shit, that wiring is genius.

[@KM6VV]

No number keys on keyboard? I suppose you could spell out the numbers.

[@KTIIbot]

Very well explained 👍👍👍👍👍

[@brianwills8689]

Thank you , that was most informative and very interesting . .!

[@writer684]

Ke? Didnt understand really but hey never saw this kind of thing before, those germans where quite clever to construct such a thin and even more clever o break it

[@James_Bowie]

The presenter failed to mention that there were at least 5 rotors in the set from which 3 were to be used.

[@kritikacharak3105]

Thank you so much! You made it so easy.

[@sheepwshotguns]

how on earth did this get cracked!?

[@NoseyNick]

Turing invented a sort of an unwound motorised version of the same machine that could be run really fast, and then stacked banks of them to compare adjacent settings simultaneously. Arguably an incredible example of early parallel processing. See en.wikipedia.org/wiki/Bombe . They could be wired in such a way as to say (for example) "run through all possible wheel settings until these first 10 letters decode as HEILHITLER" - which would be slightly more than a guess, but (given enough bombe time) you only had to guess right once per day to get the rotor settings for ALL messages that day.

[@NoseyNick]

Alonso Alonso Yes, BUT that's not enough. You need to have (or at least understand) the machine AND know today's rotor+stekker settings. Having a captured machine obviously helped A LOT, but the real genius was in turing's bombes which could essentially brute-force every possible set of rotor settings in about 20 mins. Later, when extra rotors were added, Bletchley Park geniuses worked out the wiring of the new rotors WITHOUT capturing another machine.

[@lohphat]

One major clue was that a letter would never translate into itself (e.g. typing "A" would never light up the "A" lamp) due to the fundamental design of the circuit. That gave away a large clue as to what the construction and limitations were.

[@denny.wanderer]

3DM did it

[@stabbastwhite8780]

I was the one who did it. Theoretical Physics. :.():.

[@KWatson1984]

Anybody else catch that when he says it would light a different bulb each time and he pushes it four times, it lights the same bulb three times?

[@3v1Bunny]

so i was watching numberphile ...

[@littlemikey46]

And then seven hours had passed? Yeah same thing happens to me all the time xD

[@cartermoore9362]

here too

[@pipejones1806]

Pretty cool machine, probably still used in present day

[@Emtbtoday]

There is also 3 in the US one in Vegas think the British one is the only original though they used to get smashed in the field after ww2 by Germans so alot have repo boxes and miss matched serial numbers I've seen 2 they had a pre was metal plate on them the ones durn ww2 had a sticker just under the lid

[@southernflatland]

At 10:30, message does not decode: "one thousand five hundred and seventy six" - 17,576 How do you even read that wrong?

[@2adamast]

He's a mathematician

[@tormodi5925]

08:40 I assume the producer wanted to focus on the audience at the highlight of the presentation, but apperantly from the facial expressions no one understood anything... :)

[@Nr.7-Seven]

Hmm, still the "own secret code" was basicaly useless if they got the daily code XD they would also solve that code and just set the enigma to that one. But how did they find out how the enigma works and unlocked messages if they didnt have the daily code?

[@karolynkelly-okeefe1944]

Nobody ever deciphered a single message sent by the Navajo Code-Talkers of the U.S. Marine Corps during WWII.

[@vksasdgaming9472]

Of course not as they spoke almost completely unknown, difficult language laden with weird banter which made no sense to anyone outsider. Thus in a sense it wasn't cipher in a sense and it was already used during WW1.

[@scottfuller5194]

Interesting but it was only a four rotor electrical-mechanical typewriter capable of double encryption, one for standard tactical secret work and the second level of encryption was then used for OFFICER ONLY messages ...........but the LORENZ was a fully functional automatic teletypewriter cipher machine having 12 rotors and was capable of automatic TRIPLE encryption.....used for strategic top secret communications.....!

[@ChedMoLi]

So, how can the reciever know the setting if he has very different setting in the first place? He might not even read the message in that case. 🤔

[@donshepherd2943]

In order to decipher a message, the receiver's Enigma machine had to be setup with the exact settings used by the sender when the message was created. Those settings were distributed by the Germans each month to everyone who had an Enigma machine.

[@bartek4536]

starting from ground settings xyz only to decode the letters chosen by the operator. Then, setting the new starting positions to decode the rest of the message.

[@andreasrother5234]

Explained well.

[@Fredricful]

Enn vist du har 2000 bokstaver va ser da?

[@gauravwadghule8085]

its looks like tls handshake and then securely send message

[@ruthyegudayev4703]

5:50

[@williamchen5121]

Wow. Amazing

[@JohnSmith-eo5sp]

The Enigma Cipher Machine is a mechanical pseudo-random sequence generator that scrambles a set of 26 characters

[@Warmsunset26]

A much simpler explanation as to HOW the machine works.

[@michaelmcneil4168]

Previously posted to Drachifeld's channel

[@annaberwanger4097]

Thanks so much! That really helped me!

[@matthewgrissop9408]

1,26th, A B C. B CD. CDE, example RZURZU, why 2 times, to be absolutely sure it was right