CPSC 409 Oct 21 – Transcript

00:00Okay, so I see the recording icon. Uh just a quick note cuz good portion of the recording was missed last day. What I have is electronic end of electronic part one was missed. So, I actually dug up an archive version just for that last little bit here.

00:19Uh so, you have something have me talking about it. This is on the other hand is synopsis of No, this is actually the part that I recorded last day, which includes a synopsis of the being electronic part two. And I think after about screen three or so, it goes into full details. If you find that synopsis for the beginning of electronic part two is sufficient, that's fine. But I also have an archive version of when I went through electronic part two up to

00:45I think where I ended up. It could be also useful to look at this one. So, what you should be looking at is this one to get the end of electronic part one. This one's the part I recorded, and this is an additional resource as well, too.

00:59And I recorded this so people are wondering, "Hmm, what's happening with this? How come there's three?" You can actually see that in the recording. Okay, it's just getting some Oh, that's an extra review. Not really private or anything, but lots to cover today.

01:24Okay, the role of these bombas. Right now, the bombas were a mechanical type of machine, not necessarily mechanical um type monster. As mentioned, and actually as one of the videos that I have as a link, it's actually to a movie and a very good movie. And you can you can view it

01:52legitimately. I'll talk about that. They actually give you an idea the number of combinations that are possible in one version of their encryption devices German, but they also indicates Turing actually indicates puts down some guy saying that just because you have the Enigma machine I say I have an Enigma machine then we can figure out decrypt it. No, because there's so many combinations. In a way the In one of the movies Turing is kind of presented the way he comes across he's almost like the

02:19Big Bang Theory Sheldon. He's really he he's really bright, but he's not so much for the social graces, which makes it kind of entertaining. Too many combinations. You actually have to have the hardware, but you also have to know configuration eventually change it on a daily basis the Germans.

02:38So, the Bombas were and the other devices were involved basically in trying to figure out we have the encrypted message. It compared that versus combinations to see do we actually get the proper plain text version?

02:55And even algorithmically trying to figure this out. So, I'm actually going through reviewing some of the stuff I went through the other day algorithmically trying to figure out a person, you know, paper pencil figuring out the combinations they based on the encrypted text take way too long. And again, in one of the movies um what's it called the Imitation Game?

03:15Right? I suppose it's called the Imitation Game because they were trying to imitate the encryption machines. The algorithmic methods he he kind of slaps the other guy down saying why it's not possible. And I think it's actually Turing's boss is skimming it head in the background while I was doing some work going through that review question. Turing's boss actually slaps down the other guys well, too. And he says, "In the time it took for me to actually go through this three British soldiers died. How

03:42important is this?" So, they tried other approaches Martin Rejewski they tried it algorithmically, but where they had the success was they essentially got a lot of information about the German hardware, not complete, and then they filled in the blanks. And based on that, they had the Bombes, the Brit- the Polish Bombes, to try and figure out positions. And then later on, well, the the Poles gave to the other some of the other allies their Bombes, these guys

04:11started out with these devices, then built their own versions, the improved improved versions, the British Bombes. And they were used in that process. I did some more reading about this. This actually, I believe, comes from one of the intelligence agencies, some declassified information.

04:30Here's one case where it made a major role, the decryption of the information. There's continental Europe, there's England. In order for England to Oh, well, actually, let's back up a step. England, for a while, was one of the few allies left in Western Europe.

04:50Um, and it was fighting various places, like North Africa, against the Germans and their allies. In order for them to get there, they essentially they needed um to transport their troops and equipment by ship.

05:05The problem is those um those cargo ships were vulnerable to attack, and they're specifically vulnerable to attack by the German submarines, the U-boats. Now, this is the part where they talk about the attack. The German U-boats were attacking the shipping. Also, before the US joined into the war, they're on the other side of the Atlantic, they were still helping out, they're an informal ally, in my opinion, helping out the allies, um the Brits and others,

05:32before they're knocked out of the war, the others, and they were sending um supplies across the Atlantic Ocean, important in cargo ships. Um, traveling a greater distance, those cargo ships were really poorly armored and poorly armed, if they were armed at all, so they're quite vulnerable. But what they what they're getting at here is they decrypted the German messages by determining the settings of whatever time period it was and they determined

06:00where the hunters were coming, the German U-boats. And what they the allies they didn't have enough resources to basically patrol the whole bloody Atlantic or even potentially the English Channel. But if they knew exactly where the U-boats were, they could then gather a force of specific warships that were um that had anti-submarine capabilities.

06:22Now, it's not all that have that that are good for chasing down submarines. You don't want or need a battleship to sink a sink a a little submarine. So you had smaller ships, many of them, and they could basically go where the U-boats were, and that's exactly what you're talking about, the hunters became the prey. And if you do some reading along the lines of this course, I was skeptical at first. I read that after just after World War II, Canada had one

06:48of the largest navies in the world. I thought, "Hmm, well, the population's army certainly wasn't the largest." It was largest the way China's the largest navy in the world by numbers to some extent. They had a lot of ships. They may or may not have included cargo, I don't think they did, but what they included was these smaller, cheaper ships that were specifically designed to escort, undoubtedly they were fleet escorts, escort the cargo ships.

07:15So it made a significant difference and that's that's the part you need to know for the course. And this is something new I have added here. Alan Turing, oh, yes, he is really an interesting fellow.

07:30How many of you have heard of something about Alan Turing? Quick show of hands, I'll do a survey. Know a little bit about Turing? Raise your hand. I bet it'll be a fair portion, cuz your keeners probably know Mhm.

07:46More than half. Okay, thanks. I would Oh, and still about 2/3 or so. Appreciate that. I would guess he used to talk about Turing in the CPSC 313 when you talk about these state machines, but that's no longer a required course. So, it's probably that other 300 level course that's a combination of little state machines and whatchamacallit and proofs.

08:09Notice, he passed away quite early. Very bright chap. I've actually had some discussions with Mike Williams, the who taught Proline before, and there's a I actually I I have a lot of respect for all these people throughout history. Um Turing is one of the people like um that that I have more respect for as well, too. Although, Williams had said,

08:37"Turing, yes, he was a bright chap." And he made us He can see that he made a significant difference. His contributions World War II. Um but he was quite right. He said, "Well, sometimes you read things where it sounds like Turing won the war single-handedly." I think some movies and even some online resources. I'd say, "No, I I agree with that he wasn't just just the one person broke the code." But he also added that Turing was smart, but then there's other gentleman we'll talk about, you know, John von Neumann. He said, "He was truly

09:05brilliant, but he is quite accomplished. He was no slouch in terms of intelligence and accomplishments." But and Williams also like to notice this. He produced a paper, for instance, and this is where you might have heard about it indirectly about Williams. There are some problems that cannot be algorithmically solved.

09:24But beyond that, I also find Turing interesting because he's he he's quite a unlike me, for instance, he's quite an interesting character. There's a lot of lot of nifty things about his personality. Although, he wasn't He's kind of sheltered Lincoln in a way cuz he's not necessarily, in my opinion, the easiest person to get along with.

09:46But in terms of research, known through scholars spending year the Ivy League Princeton, met various the off aforementioned John von Neumann, which we talked about in terms of um computer memory. Einstein, the Einstein we're talking about.

10:02And he worked at Bletchley Park as a code breaker. He contributed He basically He had pushed one people had pushed for not solving the problem, essentially trying to figure out the configuration of the encryption machines um manually because he saw it it wasn't practical, but doing it with some computational devices. Now, it wasn't all just

10:26machines. He also applied some his um analytical problem-solving skills as well, too. Oddly enough, um what's his name? Williams said, if I recall, with Turing that although he contributed a lot to the design of these machines and later machines, he was apparently a real klutz and a disaster in lab tripping over and breaking things accidentally.

10:50An eccentric person. Okay, now this is going to be off the record here. And the pure scholar part, the more like the bookworm rather than the street smarts.