I was fortunate enough to hear Dr. Tutte give a talk in one of my undergraduate classes. It was Fall 2001 and I was a lowly undergrad at UW taking Math 249, the "advanced" requisite combinatorics course. I believe Dr. Tutte was a professor emeritus at the time and came to campus about once a week. Since our class was small, our prof asked us if we'd like to have Dr. Tutte give a talk. To be honest, I'd never heard about him before that, but the idea of having a math prof who helped fight Nazis come in was kind of awesome.

I still remember that talk to this day. The actual content of the talk was very interesting (he talked about his work at Bletchley Park, coming to Canada, his research at UW), but what has stuck most in my mind all these years was what I can only call his aura. Even at 80+ years old, he was a captivating speaker and all ~ 20 of us kids in that class were slack-jawed, hanging off our seat, listening to every word, in awe of him and what he did, especially since he wasn't that much older than any of us were when he did it.

I later did work with mesh parameterization and was delighted to find out that his work was considered seminal (the planar embedding theorem and the so called "Tutte weights"). He made a lot of contributions and published a lot of material, so I guess I shouldn't be so surprised that my area of research intersected with his. It was a nice feeling to be able to reference him though.

To his memory.

I was fortunate enough to go to Blethcley about ten-ish years back when the war time crpytanalysts were doing guided tours (do they still do that?). I forget the name of the bloke who escorted our group around, but it was well known in connection to the place.

As another UW Math/CS Alumni. I think one of the reasons the Combinatorics and Optimization department is so strong is because mathematicians like Dr. Tutte laid down the foundations so very well in the early days.

There's a good book out - http://www.amazon.com/Colossus-secrets-Bletchley-code-breaki...

The book talks about Tutte and Flowers and how they went about building the world's first true computer. It includes schematics and algorithms and other technical details of the machine. Actually, if you're old enough, you probably remember getting told in your first CompSci classes how computers were made up of I/O, a CPU and memory, which even by the 1980s seemed like a quaint way of viewing things. Reading Colussus for the first time, you really understand why they made the distinction in the textbooks. Just the machines to read and write to paper tape were incredibly complicated, and the speed that you could spool paper tape was a limiting factor in the early days. Indeed the first systems didn't really have a memory system, they had to keep re-reading data from tapes. The need to avoid that was the reason they invented memory in the first place - it sped up computer operations by orders of magnitude!

The book also covers in great detail how they went about intercepting the signals from the German High Command - which itself was a very modern digital modulation scheme that hadn't existed until them. The work of the signals interceptors was very impressive too, and run by the British Post Office, if my memory serves correctly :D

If my memory serves, the German High Command were using teleprinters and were sending the teleprinter signals via radio. This did sound totally different from Morse (which was used for other signals, such as those encrypted with Engima), but I don't think this was very new.

The transmission technology was RTTY (http://en.wikipedia.org/wiki/RTTY) which was active well before the Second World War. It would have sounded odd to Morse operators, but would have been recognizable and easily decoded as it is just FSK.

It's been a while since I read the book, but I thought the modulation scheme was a form of QAM, which was new at the time. The book certainly emphasizes that it took the interceptors quite some time to realise what they were seeing. Still, my memory of the details is a bit fuzzy, and I know that you have researched this area quite extensively, so I defer to greater knowledge ;)

Another interesting code breaker during WWII was the Swede Arne Beurling (https://en.wikipedia.org/wiki/Arne_Beurling). He reverse-engineered the Sturgeon cipher from intercepted enrypted texts using pen and paper only, enabling Sweden to break the cipher systematically.

On the other hand, this had little impact on WWII as a whole, so it is not as important as the code breaking done at Bletchley park.

Don't forget about people who were breakine enigma 'before it was cool', and they succeed: http://en.wikipedia.org/wiki/Bomba_%28cryptography%29, http://en.wikipedia.org/wiki/Marian_Rejewski.

True, but this story has nothing to do with Engima.

Not entirely. The article does make some inaccurate claims about the cracking of the Enigma.

Can you please clarify what you mean?

The story about Bill Tutte has nothing to do with Enigma. Yes, Bill Tutte worked at Bletchley, and so did the code breakers who worked on Enigma.

But Tutte worked on Lorenz, and this story is about Tutte and his work, and hence this story is not about Enigma.

while not Enigma related, Marian Rejewski and his colleagues, if I remember right, reconstructed physical Enigma (pre-war, 3 wheel) machines only from analysis of encrypted traffic, beating the French and English mathematicians working on the "enigma problem". it was pretty big and IMO comparable to Tuttes successes with Lorenz, it's annoying that history forgets Rejewski and his contributions so quickly.

More accurately, the British and French had not managed to make any progress decrypting the Enigma until the work of Rajewski and the Biuro Szyfrów was handed over to them due to the shifting political situation.

I was fortunate to have dinner with him once when he visited our University (sadly, this was close to the time of his death). He was a pretty sweet old man. I recall he was very humble and a vegetarian. I had no clue he was so accomplished until I took a graph theory course in grad school!

How I wish I could upvote this more than once. One of my heroes - wonderful mathematician, phenomenally clever, incredibly modest.

His Wikipedia page is definitely worth a read to get a more balanced picture of the scope of his work:

https://news.ycombinator.com/item?id=5779247

Agreed. And also everyone talks about Enigma but in many ways it was the end of the line of cryptosystems.

The Lorenz cipher that Tutte broke is much closer to today's ciphers. It was a pseudo-random number generator whose output was XORed with the message to be enciphered (which had been converted to Baudot code): http://en.wikipedia.org/wiki/Lorenz_cipher

Very similar to RC4, for example.

And Lorenz worked by exploiting co-primality to achieve a long key stream.

Also a contributor to discrete math while teaching in at waterloo (graph theory and combinatorics):

http://en.wikipedia.org/wiki/W._T._Tutte#Doctorate_and_caree...

Hear you can hear the man himself speak (RealPlayer and a lengthy boring introduction though, not for the impatient)

http://www.fields.utoronto.ca/audio/01-02/CRM-Fields/tutte/

Whenever someone talks about Alan Turing as just a "code breaker" I cry a little

Interesting. I'm familiar with Tutte's work in graph theory & matroid theory. I had no idea he'd been at Bletchley Park. He seems to have done an awful lot of very significant work.