Fishy Codes: Bletchley's Other Secret - Computerphile

[@oneofspades]

Professor Brailsford deserve his own channel.

[@ScottStruzik]

I could listen to Brailsford talk about computers for hours.

[@ztoob8898]

Agreed. He's great!

[@woodywoodlstein9519]

I would have given my left nut to take a course by professor B.

[@iainwalker8701]

i have listened to him talk for hours over the last few evenings. he is a fantastic story teller and really draws you in to the topic

[@auntiecarol]

Ditto, much to the annoyance of the missus!

[@tomheynemann8768]

The David Attenborough of computer documentaries...

[@GoSlash27]

9:00 I really struggled to get my head around this part, so I started playing with it and figured it out. What's happening here is if you use the same key on 2 different plaintext streams to produce cyphertext and then XOR those 2 cyphertext streams together, they will produce the exact same result as if you had XORed the original plaintext streams. So if you can guess the plain text in one stream and then XOR with the common stream it will yield intelligible plaintext in the other. You can use both encrypted streams to decode each other. Once you have a full plain text, you can XOR it with its cyphertext and it yields the key. HTHs, I melted my brain on it.

[@axlepacroz]

nice to see another vid about the lorenz machine, fascinating stuff. They worked out how the the machine worked even without seeing one. It's insane, how clever these guys were

[@aminaleali7161]

What a great story teller! Thank you. When I watch his videos, I feel as though he knows my level of understanding and he's only talking to me.

[@gasgas2689]

They were called Y stations because Y is the quick way of saying WI stations - Wireless Intercept stations. Also a lot of traffic was broadcast by radio because the French Resistance were busy blowing up telegraph poles and cutting telephone lines. They did this specifically to force communications to be sent by radio, which can easily be intercepted.

[@terapode]

Professor Brailsford´s body language is so amazing. He comunicates not only with words but also with his mannerism.

[@RoamingAdhocrat]

and in encrypted morse code from his eye blinks

[@RMoribayashi]

Radio teletype AKA RTTY has been a popular mode for radio amateurs since the 1950's. A few experienced RTTY operators can actually convert the warbling tone to words by ear. It's similar to decoding fast Morse code where entire words are recognised by their unique sound.

[@bborkzilla]

According to Jack Copeland's book "Colossus" Bletchley was known as "Station X" because it was the 10th of several stations set up by MI6, all of which were assigned Roman numbers.

[@michaelwoodhams7866]

The Japanese codes were book based rather than machine based, and had code books (changed every so often) and a big book of 'random' numbers (also changed every so often) which were used as an additive cypher on top of the codes. The issue of depth with additive cyphers was much more prominent in the Pacific cryptanalysis. The additive cypher book was short enough compared to total traffic to build up considerable depth, but whereas for Tunny the layer under the cypher was plaintext, in the Pacific it was code words, so depth alone did not solve the problem.

[@tatianatub]

decrypt your enemies data with this one weird trick cryptologist hate this guy

[@oliverutriainen2837]

ashley beaumont your text felt good when I read it. thank you for that.

[@thewhitefalcon8539]

Nowadays, unbreakable encryption is common knowledge

[@ZekeRaiden]

I'm super late to the party on this one (re-watching this video for the zillionth time), but apparently the "Y-Service" (from which the stations got their name) were monitoring wireless traffic, so "y" was short for "wireless." (Much as we shorten it to "wi-fi" today.)

[@U014B]

I thought it was going to go more like Dr. Brailsford: "They were called Y-stations." Sean: "Why?" Dr. B: "Yes, that's right."

[@ThomasNimmesgern]

;-)

[@DavidChipman]

+Noel Goetowski LOL, shades of "Who's on First".

[@NPC3.14]

Wi?

[@AgnostosGnostos]

Tommy Flowers, the creator of Colossus first electronic computers died in 1998. Yes in 1998 long after the end of the Soviet era and during the expansion of internet in every home. It was a serious mistake that he wasn't Knighted. W. T. Tutte (Bill Tutte) died, another important person of the Colossus mentioned at 6:55 died even later in 2002 and wasn't knighted either.

[@charlesmiller000]

Hooray! Professor Brailsford continues on from Enigma & Colossus. Personally, as a computer scientist, I am scarfing up everything he puts on KZbin. Thank you!

[@Mohamed.GadAllah]

May you add the videos you find for him on a playlist and share it with all of us.

[@TommiHimberg]

Prof Brailsford's excellent explanations of codes and ciphers continue. Now we start to delve into how the Lorentz system worked, and how codebreakers in Bletchley Park broke it.

[@Mendelmandela]

We need this brilliant Professor here in Kenya at the university of Nairobi school of computer science

[@Quimbyrbg]

Fantastic stuff, I am loving your coverage of WW2 cryptography. The Colossus team surely did miss out on the admiration they deserve.

[@Wamfox]

Love it, slippage like you have never dreamed of in your worst nightmares

[@CalMariner]

Watching this in rapt attention - his storytelling is amazing, and the history of the incredible minds behind these codes is fascinating!

[@OnlyUseMeEquip]

the david attenborough of code

[@dacramac3487]

They were called Y-Stations because it was a sort of pun on the initials of Wireless Interceptors (WI with the I pronounced as eye).

[@alizaidanthamyeez740]

Once when I was playing Minecraft and creating redstone creations I was getting bored with the normal stuff and I got the idea of using logic gates to encrypt characters. After theorizing, creating and testing the redstone machine I used it for quite a while and then I watched this video and found out that I, without realizing ended up creating a Vernam cipher

[@magter3001]

Just found this channel, and boy am I happy I did. :)

[@DrysonBennington1]

Y Stations = two electrical inputs that create a single electrical current that is then divided again at the end source to create the desired letter or number based on what else? Wheels with two sets of dials for each set similar to the Enigma machine had. Y + X = YX or WhyEx or Wix. Two Y's pushed together create an X with the tail forming in the middle to create a W path accept the tail of the Y creates two Right Triangles. So Y and X have the same meaning mirrored 90 degrees to the other.

[@stevem9529]

I think its just short for WIreless

[@sclabhailordofnoplot2430]

So Y stations were British signals intelligence names for Radio sites. X for Bletchley was according to google sources for it being the tenth Y site built.

[@BTHobbies]

This series is so cool! Thanks for keeping these coming!

[@MaxJNorman]

Up there with James Grime and Ed Copeland in my opinion. Great guy.

[@dbatdev]

Ace storytelling. Can't wait for the next tale.

[@ImSquiggs]

I fell down a Computerphile hole two weeks ago and I'm still not out of it

[@grn1]

I think it's been a month for me.

[@TheSlimyDog]

I love learning about the history and stuff but I'd prefer to hear a bit more about how this stuff worked and what those vulnerabilities were and how they were cracked.

[@seanski44]

That's all coming!

[@compu85]

+Sean Riley Was the follow up to this posted?

[@roderik1990]

+compu85 It's the Zig Zag Decryption video.

[@Starchface]

Funny thing-I just finished a can of tuna. Coincidence? I think not. I imagine Professor Brailsford spent years or decades teaching so it does not surprise me that he is so good at this. Presumably he is retired, so you can continue to mine that massive brain for years to come.

[@EtzEchad]

With modern technology, you could make a Vernon cipher (actually a code) which doesn't repeat for billions of bytes. Of course, you would have to find a secure way to transmit the code disk to the recipient. The thing is about codes, is that they are unbreakable if you don't use the same code string. (I'm sure that this technique is standard today. I do know that very little encrypted traffic is broken nowadays.)

[@BlurryBit]

Wish I had a grandpa like this. Pretty much the big picture to what I am aspiring to be for the last 12 years. :D

[@GoldViolinFlutist]

I wonder if people used multiple factor cryptography, like for example, scrambling a message with enigma and then sending that via tunny code

[@linkVIII]

My proffesors are fine but I much rather listen to Brailsford

[@Tactical_Hotdog]

linkviii I bet they'd be impressed that you can't even spell "Professors".

[@linkVIII]

Tactical Hotdog Who in cs cares about spelling?

[@intelX1000]

+linkviii Everyone. English is the most commonly known high-level programming language.

[@linkVIII]

:^) Snowman Face With A Caret For A Nose :^) Turns out the word professor isn't used much in technical writing. Though my lecturer in my tech writing is incredibly picky on word choice.

[@Angloth]

Its in fact so high level - that youre acctualy not reqwired to wright it cerroctly iN odrer for u 2 understen

[@cigmorfil4101]

BP was called station X as it was the tenth such place, the others were Station I, Station II, ..., Station IX (the station number being in Roman numerals).

[@dankswtf]

Love these videos, very fascinating :)

[@gonzo_the_great1675]

BP had a Y station. Station number 10. X in roman numerals. Hence station X.

[@EuroCrisis2012]

Why were the radio signal collection stations called the Y service? Here is the answer. It is the British sense of humor. They were collecting "WIreless". The "Wi" became "Y".

[@Cygnus0lor]

Actually, it was Wireless Interception (WI) towers. But overall yeah true. Funny innit?

[@DrRChandra]

Just a little trivia: If you look at the filename of the APK for Android's Dolphin Browser, it looks like at one time it was called "Tunny."

[@anthonyfrancis-jones7059]

Y Stations... (listening stations), sure this is a long shot but it is rather nice that the electrical symbol for an antenna is very similar to a Y. Just a coincidence I guess.

[@spyguy318]

This reminds me of Number Stations. These Tunny Transmissions were the first number stations!

[@ohgosh5892]

The enigma stations were the first number stations, lorenz was second.

[@RobinWootton]

Terrific

[@World_Theory]

I need more tunny. I don't eat enough of it.

[@lauriepocock3066]

Please can somebody clarify for me. My understanding is 1)you add the chi (constantly changing) to the plain test, but the Germans were concerned that this result could give to many consecutive dots and plus's so- 2) they added a second stage set of wheels (psi) that only change depending on the result of exclusive or(ing) PT to chi.

[@buck7271]

so wait, wheres the second video?????? where?

[@jibberjabberman]

fantastic!

[@Bograff]

Is there a reason they couldn't reprint the 2 tapes at 5:20 onto a single 10 hole tape so they don't lose synchronization?

[@avro549B]

+Bograff That would have needed a supply of the double-width tape, and the hardware to handle it. It probably wouldn't have been very economic to create that infrastructure just for encryption, though I suppose cash-register tapes might have been used. (The 5-track stuff would have been produced in enormous quantities for routine applications.) Technical developments are often shaped by what's cheaply or conveniently available. E.g. early punched cards were the same size and shape as $ bills, because there were already dollar-bill handling machines.

[@U014B]

+ProfDaveB Wait, are you the man who narrated for "Look Around You" (first season/"series")?

[@5hape5hift3r]

why not multiple shorter encryption keys that are all coprime length

[@raijinmeister]

And people thinks the Eletronic Warfare,is something new.

[@spiros1994]

The professor has affected and influenced I guess by the current situation in Greece and uses it for example :-D

[@BillDavies-ej6ye]

Station Y = WI = wireless interception.

[@spiros1994]

Maybe they called them "Y" stations because of the antenna symbol which is like a "Y".

[@Patmorgan235Us]

spiroslouis1 or y = x + suff

[@sundhaug92]

spiroslouis1 Would be too easy to guess. I'm presuming it's named from the reverse alphabet (first would be Z, second Y, third X and so on)

[@owenwilliams9666]

spiroslouis1 I think I heard somewhere that the 'Y' in Y stations was a corruption of 'W'ireless stations. Bletchley Park was called Station 'X' as it was the 10th station so named.

[@UberAlphaSirus]

Great stuff, just as good or better than the bbc radio 4 sitcom. :)

[@jack002tuber]

At 9:07 you said the additives have a weakness. If your key is several thousand bytes, that should eliminate that.

[@DzheiSilis]

jack002tuber Have fun doing that in 1940's tech

[@jack002tuber]

Its easy in 2016 tech, I live in 2016

[@jack002tuber]

Google ONE TIME PAD, they did it in 1940

[@davidcreagh]

I seem to remember that the sorts of antennas that the "Y Stations" used looked like a letter Y.

[@joe564338]

This guy rocks

[@seamusandpat]

Brilliant again, I love these histories. More please. :D

[@RoelfvanderMerwe]

This guy is so sweet. I love him!

[@iabervon]

One of my problem sets in school had us decrypt a pair of documents XORed with the same random sequence. It was rather disturbingly easy.

[@ohgosh5892]

Maybe you should tell the Bletchley crowd how easy it is.

[@iabervon]

@@ohgosh5892 As he says, they found decrypting the pair they got really easy, and they were particularly looking for the Germans to make that mistake because they knew it would be easy to decrypt.

[@msimon6808]

The Americans actually had a one time tape machine. SIGTOT. So the tape problem was not insurmountable.

[@oracleofottawa]

First lesson that you learn as a naval "sparker" NEVER SHRED THAT PLASTIC TAPE!! LOL...

[@BEP0]

Nice.

[@AbdiPianoChannel]

Very impressive. It's James bond thing

[@LAPGOCHINSTRUCTOR]

Y stations got their name derived from Wireless Interception (WI)

[@RoamingAdhocrat]

why?

[@woutervandervoort9088]

lol , sound like : x is receiving and sending and y is only sending station ,

[@tschak909]

Lorenz cipher attachment for a teleprinter...

[@chasemarangu]

At 0:09 literally, the enigma lol! not figuratively like a puzzle.

[@chasemarangu]

At 1:40 lol I can't do that noise

[@TheNikiNeu]

Damn it

[@RoamingAdhocrat]

You don't know Y?

[@wyrmhand]

Next part is Zig Zag Decryption

[@massimookissed1023]

Two words: Linear Feedback Shift Register

[@demonetizeddemonetisedinmy1890]

but that's four

[@Haerton]

@@demonetizeddemonetisedinmy1890 Two words: 'Feedback'

[@rjfaber1991]

That's quite funny then, that both Enigma and Lorenz were ultimately broken because of lazy Nazi operators...

[@Quimbyrbg]

+Robert Faber Always remember to explain to your staff why rules exist, otherwise they won't know why they should follow them.

[@cigmorfil4101]

The Lorentz definurely, but Enigma was usually cracked due to Enigma's design and use of cribs, usually derived from military protocol. The problem with Enigma was that no letter could encrypt to itself (caused by the physical mechanism itself). The wheels and their wiring was well known. To crack Enigma the boffins took then encrypted stream and tried a crib; from this a "menu" was generated which was fed into a "bombe" which was loaded with all permutations of the known wheels and then run to find what setting would create the crypt from the plaintext - effectively running 30 enigma machines (each one set up in every possible permutation) in parallel. With Enigma the laziness dramatically reduced the time to decrypt as the key was effectively given. The navy enigma used 4 wheels instead of 3 from a larger pool of wheels. Also grabbed was the setting sheets so it reduced the amount required to find the key.

[@bernardusmuller1109]

People that don't know how important Cryptocurrencies are should watch this.

[@therugburnz]

Oh yes they are. Circa ww2

[@dannygjk]

I bet almost zero people these days know anything about codes and ciphers.

[@jeroenkluskens]

V.v.V

[@MrTgaffaney]

First

[@NPC3.14]

First reply to first comment!

[@arrancockroft2834]

Compute .., 😂

[@arrancockroft2834]

F b shy ha ha

[@gummipalle]

Do we really need all this war junk? I feel like I get enough of that everywhere else... Surely there are some computer related subjects that dont have to involve millions and millions of deaths and global domination and all that boring crap... -I mean, we've already had plenty of enigma stuff... Cant we leave those things to the war-guys? There are already thousands of channels for that....

[@MichaelMedlock]

+Frabbledabble "war junk"? This is computer science through and through, put in historical context...

[@MichaelMedlock]

Frabbledabble Computerphile has dozens of videos that have nothing to do with war. Not to mention, death camps? There's not one mention of death camps...

[@malisa71]

+Frabbledabble No. And the war-stuff will get even better because humans do not change, so there will be another war where after it technology will change.

[@malisa71]

Ok. Fair enough. So why did you watch a video about "hitlers enigma" ?

[@MichaelMedlock]

Frabbledabble You're free to not care. But wars *do* happen, and ignoring them does not change that fact. Learning from them helps to prevent them however.