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How Allies Used Math Against German Tanks
Pepebuho writes "This an article about how the allies were able to estimate the number of German tanks produced in World War 2 based on the serial numbers of the tanks. Neat! Godwin does not apply."
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If I want to quote Mike Godwin, you quote-Nazis aren't going to stop me. All he said was, the longer an Internet discussion goes on, the more likely it is that someone will mention Hitler. Well, duh.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Note to self for world domination plans: don't stamp my robots/tanks/drones with plain text serial numbers, always encrypt! :-)
Also the first tank serial # should not be 1.
Try something like 24370239.
If I were God, wouldn't I protect my churches from acts of me?
Here's the original source... from July 2006.
You know who else was able to estimate the number of German tanks?
SSC
I have an uncle with a small lighting business. He has one truck, proudly labeled #6. I guess the German's didn't think about their tanks as an advertising canvas.
This is very similar to the method that the CIA used to get a seat at the Big Boys table in U.S. Intelligence operations in the 1950s. When OSS became the CIA after WWII, they became a junior member of the U.S. Intelligence operations. In the 1950s, the Defense Intelligence Agency (I may have the wrong department, but it was the organization that got the lion's share of the U.S. Intelligence budget) estimated how many intercontinental bombers the Soviets had by looking at the size of the factories where they produced them and estimating how many the U.S. could produce in a factory of that many square feet. The CIA wanted to get a bigger chunk of the Intelligence budget, so they started looking at satellite photos of the Russian bombers. They noticed that the numbers on the tails of Soviet bombers went 1, 2, 3, 4, 5....11,12, 13, 14, 15,...21, 22, 23, 24, 25, etc. Based on this they determined that the Soviets had many fewer bombers than earlier estimates. When other sources provided corroborating evidence, the CIA was able to get a bigger chunk of the Intelligence budget. Of course, they then made the same sort of mistake in estimating ICBMs that they had corrected with this methodology.
The truth is that all men having power ought to be mistrusted. James Madison
Don't be so dismissive. Knowing how many tanks the Germans had in total is related to knowing how many they can marshal in a particular region. Also, part of the allies' goal was to figure out how many tanks the Germans could manufacture. If that number was high, then the Germans could have bolstered an undersupplied and perceived-to-be-weak region.
To be back on track, the math involved is pretty straightforward. For those interested, the Wikipedia article has more information on the subject.
It can work backwards. At the Battle of Verdun in WW1, Petain (who only became an anti-hero in WW2) rotated French regiments through the Verdun front (a system called noria) so that whole regiments would not be destroyed. The Germans left their troops in battle till all were killed. From captured French uniforms and the number of regiments recorded, they greatly over-estimated the size of the French defense.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
I am implementing this at my factory. In fact, tanks c4ca4238a0b923820dcc509a6f75849b, c81e728d9d4c2f636f067f89cc14862c, eccbc87e4b5ce2fe28308fd9f2a7baf3, a87ff679a2f3e71d9181a67b7542122c, and e4da3b7fbbce2345d7772b0674a318d5 just rolled off of the the assembly line.
Actually, I think the best course of action would be to stamp false serial numbers / easy-to-decrypt serial numbers. Giving the enemy false information is likely better than none at all.
Of course, I guess that means the "real" serial numbers will have to be encrypted...
Reminds me of the prank where you release 3 goats with the numbers 1, 2 and 4 on them and watch while everybody searches for the one with the number 3 on it.
256 tanks per turn? Impossible! That would take a regular supply of 1280 IPCs...
Not to mention, if you have an idea of how much total strength the enemy has, you know how committed they are to a location where you know their strength. If your enemy has 90% of their estimated force in one location, you know that you can (if you want) hit them with a counterattack in another location unopposed.
The information is far more relevant than the GP thinks.
"16MB (fuck off, MiB fascists)" - The Mighty Buzzard
The mistake they made was looking at middle manager numeric metric goal achievements. Anyone in modern corporate America knows it possible to generate amazing numbers, yet not really accomplish anything.
I have faith they were meeting the appropriate metric goals at a 1400 tanks/month pace for diversity training, staff meetings, coffee consumption, memos distributed per week, slashdot first posts, etc, yet at the same time have faith that they only shipped like 5 working tanks out the door.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
My dad drove a tank in WWII. I believe one of the Churchills but I'm no war historian and I'm happy to be shown otherwise. He was in the Normandy landings and eventually in the invasion of Berlin too.
Thing is, the German tanks had bigger guns and longer ranges - significantly longer. There was apparently a speed advantage to the British tank (I'm going by what I was told, again I'm not a WWII-buff by any means) though, so what they used to do was lure the German tank into a village, then drive round back of them. The German guns were so big they couldn't turn them in in a normal street with buildings on either side whereas the smaller British tank certainly could. Not sure this was by design, but they took any advantage they could of course and I'm told that this trick was used by my dad a number of times.
Cheers,
Ian
Hell, if Hitler had just had better weather there's a good chance you'd all be speaking German right now. Those of you that survived, that is.
NO CARRIER
Yup. That's the Nazis in WW2 alright.
Knowing tank concentration is NOT vastly more important than knowing the rate of tank production.
Adapting to tank concentrations invokes relatively short term planning concerns. This information is needed to help you decide your counter-concentrations. You know what they have and where they have it, and then you move your stuff in response.
But tank production is HUGELY important. You're talking about EXTREMELY complicated logistical problems there. How many tanks are you going to manufacture in response (lag time)? How many bombers are you going to allocate / train for heavy industry attacks (lag time)? Are they making so many that you've got to come up with a replacement for the Ronson Tank (big lag time)?
World War 2 took a long time. Long range planning was super-important. They didn't have computers. Anything that could make the strategic position clearer was very important. The other poster is right: You shouldn't be dismissive. This was a big deal and some geek's idea helped win the war.
They were Germans. Case settled.
To this day German castles are restored to what they looked like in what ever year they want them to look like because they recored the location of every thing and number all the artworks and other items.
I am implementing this at my factory. In fact, tanks c4ca4238a0b923820dcc509a6f75849b, c81e728d9d4c2f636f067f89cc14862c, eccbc87e4b5ce2fe28308fd9f2a7baf3, a87ff679a2f3e71d9181a67b7542122c, and e4da3b7fbbce2345d7772b0674a318d5 just rolled off of the the assembly line.
You should at least use some salt if you just use md5 on those serial numbers... I could decode your serial numbers just by using publicly available reverse md5 lookup table...
The wars in Iraq (which is all but over for the US, good luck with that INA) and Afghanistan are very different from World War Two. If the US had fought Vietnam, Iraq or Afghanistan with the same disregard for civilian casualties and overwhelming firepower there wouldn't be a problem.
Modern Mindset - Isolate Fallujah, tell the civilians to get out, then go house to house to secure the city with Marines and Army.
World War Two Mindset - Mass on one side of Fallujah, carpet bomb the far side of the city for a couple days, then send infantry in supported by artillery while blowing blocks up, block by block until no one is left to resist. Or, firebomb the city with incendiaries, or bombard with artillery for days before going in, like Casino. Any one that flees, harass with airpower and/or chase down with armored cavalry units
Right now if a shooting war broke out between the United States and today's Germany or today's Japan, it'd be no contest, although Japan has a better military right now, the US would win.
The last time the US really went all out was the ground war to take Kuwait at the end of Desert Storm, and even that was just about 1/3rd of the total air and naval power and about 1/2 of the ground forces. The US military has become much more lethal in the 20 years since Desert Shield started.
I read the title as 'Meth':
For once a misreading made perfect sense in the summary title's context: use of amphetamines throughout World War II on land and air personnel is well-documented. There's a phrase one hears infrequently that amphetamines 'won the Battle of Britain' - fending off constant attack from the Luftwaffe made necessary the use of stimulants as hiring and training a new pilot took too long. Whether it really did tip the scales in that battle we'll never know. As one would expect abuse orose within both Allied and Axis forces, and the spike in use persisted after the war. The Vietnam conflict saw American troops use methamphetamine very widely, and today the drug is popular amongst the poor as a relatively inexpensive stimulant.
If there's anything that isn't widely known by the public and merits publicizing it's history of drugs such as this in the context of 20th century events like warfare. What laid ground for a forerunner to the modern drugs situation to me represents a phenomena of greater gravity than the serial numbers of tanks which one would expect would be used simply through using good old oxymoronic common sense.
Presently there's a drug by the name of 'Modafinil' which mimics amphetamine but removes almost entirely the euphoric element and much of the crash that accompanies sudden cessation. It has been around for a number of years, and sees much use in modern conflicts. It also has much off-label use, and has even been used by astronauts to cope with heavy exercise regimens.
You mean the prank where you release 3 goats, and everyone just looks at you and says "Wow, sucks that your goats got loose. Good luck catching them," and then goes back to playing beach volleyball?
The enemies of Democracy are
What was the number of the first tank? zero, or one?
The Kruger Dunning explains most post on
How about a small integer k times the real serial number plus a uniformly distributed random integer from 0 to k-1?
--
Mein Herr,
Your application for Grammar Fuhrer is rejected. You are otherwise highly qualified, but the post is occupied.
the only information needed to make this mathematical method work is that the serial numbers be sequential. As in auto-incrementing. Which is not data in a serial number.
but nevermind the facts, let us reconsider instead the choice to use or not to use 'intelligent' serial numbers back in 1942. Because it matters.
The world must know if the Nazi were bad database designers as well as genocidal sociopaths. Possibly the two are causal? No? Well, It was a theory.
Maybe some of the tradeoff costs have changed in the last sixty years or so? Maybe the costs of data storage or data retrieval have changed?
We'll never know. Hitler took the master copy of the Nazi database normalization guidelines into that bunker with him and they were never seen again.
With just as many nukes pointing to the US, I'd not be so sure.
The Tao of math: The numbers you can count are not the real numbers.
Reminds me of the prank where you release 3 goats with the numbers 1, 2 and 4 on them and watch while everybody searches for the one with the number 3 on it.
I'm a programmer, I'd be looking for the one with number 8.
A biologist, a physicist and a mathematician are visiting a foreign country. As they leave the airport in their car, they pass by a field, in which stands a single, black cow.
The biologist says, "How interesting. The cows in this country are black."
The physicist says, "You can't say that with certainty. All you can say is that they have cows in this country, and that at least some of them are black."
The mathematician says, "You can't say that. All you can say is that there is at least one cow in this country, and that at least one side of it is black."
Do I need to explain the relevance of this joke
The system was used for something like sending pictures of suspected card counters and other cheats back and forth
Card counters aren't cheats, it's just that casinos don't like them because they do the same thing with skill that a casino does with manipulating the game. If anything, the casino is cheating.
Only morons put data in a serial number, it's one of the most fundamental mistakes of database planning.
There are lots of valid reasons to put data in a serial number -- especially in 1941.
If you're maintaining a battalion's worth of tanks, it's useful to know where your tank was manufactured and if it was manufactured around the same time as the other 5 tanks in your battalion that had bad drive gears.
It's not like they could have done a simple database lookup to find the assembly history of each tank. And generating a unique series of serial numbers across multiple factories would not have been trivial.
Of course, they ended up in inadvertently revealing secret information, but maybe they didn't think it was all that secret and assumed that observation alone would provide that data. (which didn't turn out to be true).
1) md5 is a trapdoor, therefore there are many possible source values for any given hash value.
2) Given guids, good luck building a suitable lookup table.
1 and 2 stand independently of each other :)
char*f="char*f=%c%s%c;main(){printf(f,34,f,34);}";main(){printf(f,34,f,34);}
That's exactly why the Soviet Navy gave their ships non-sequential pennant (hull) numbers, and frequently re-assigned them. They would also sometimes paint one number on one side of the bow, and different on the other.
Security is a difficult business.
Intelligence can also be a weird business... I once read an account of how the CIA broke into a warehouse rented by the Soviet Embassy in Mexico City in order to examine (very closeup and very clandestinely) a high fidelity mock-up/prototype of a satellite the Soviets had on tour. The idea was to gather information on any real cable, connectors, or other hardware on the bird - as well as to collect any serial numbers, drawing numbers, etc.. that they could find. (It's not uncommon for such to contain 'real' items that have been discarded from production or operational use.)
You'd be surprised what a trained and knowledgeable analyst can derive from just a few seemingly unconnected bits of information.
If the Nazis had taken Britain and the Caucasus, what do you think are the chances that the US would have tried to invade from across the Atlantic? It's one thing to island hop the Pacific; it's another to jump the entire Atlantic in one go.
That's the thing though. We were fighting Germany and Japan. We're not fighting Afghanistan, we're fighting Al Qaeda. If you firebomb cities in Afghanistan, you're mostly destroying your allies. It's an entirely different sort of war. It's a war you don't want to fight because it's almost impossible not to make a huge mess and accomplish nothing.
If North Korea decides to invade South Korea, that's the sort of war we can fight. One with a clear goal and somebody who has the kind of authority needed to stop hostilities once you negotiate a peace (even if it's unconditional surrender). You can't do that with insurgencies, because there is nobody in charge and they're run more like criminal gangs than actual armies.
I read the internet for the articles.
You would get collisions, is why. Very dumb idea.
So what? If you're tank can't take a few collisions, then you've got serious problems.
When our name is on the back of your car, we're behind you all the way!
You may consider them morons but they didn't have the benefit of your knowledge.
If you look at the VIN number of your car, it still has plenty of information in it. Lets pick on a relativity recent Chevrolet for instance. The information can tell you where it was made, what options was installed from the factory, what motor came with it, what year is was produced and so on. Unlike a serial number in a database, on material items it's important to carry some of this information in order to track down problems with a specific portion of the assembly or whatever. In the situation with a tank, if the main guns jam on a regular basis, it might be that the boring tool for the breach is undersized slightly so correcting it would require a recall and retrofit of all tanks produced in that plant with that bore tool.
The benefits of knowing is way more important then someone possibly finding information out, especially if the information is obfuscated in some way with a code. Unfortunately, this changes when there is a war and the equipment is used in that effort. If that code was ever broken, then you can learn a plethora of information like if it's a new plant making a certain part or the entire tank, if it's a plant that has a large production capability (making it a prime target for industrial bombing), and so on. And just like the information buried within a VIN number, most people aren't aware of how to decode it making it appear as some random number sequence. It's really a lot like communicating war plans in code, you don't think it's compromised until you realize someone is acting on the information within the code.
And yes, since the serial numbers were for long term tracking, it's not like a database at all where a random number can be used more then once as long as the sessions aren't still active. It needs to be a unique number dedicated to the piece of equipment and regardless of how you randomize it or attempt to obfuscate and information, a pattern will ultimately develop that can be somewhat useful to an opponent. You have to remember, this is before computers and humans needed to be able to track the assets by hand, often from far, far away.
I've been telling people for years that WWII really came down to a battle of quantity over quality. Technologically, Germany was 10 years ahead of everyone else. Furthermore, their weapons were amazingly well-engineered. But they didn't have the facilities and infrastructure to produce in large quantities.
And that's what the USA had -- tons of natural resources, lots of factories, lots of fairly untouchable infrastructure with which to crank out a lot of weapons. Never mind the weapons were of inferior quality (i.e. The Sherman) we just had so many, we overwhelmed the Germans with the sheer number.
And what WWII American doughboy didn't desire a Luger pistol off any captured German soldier? That shows the quality of the German war machine, everybody wanted their stuff.
Witness how the American Forces and the Soviets were both racing to capture as much German technology as they could once it was clear the Nazis had lost the war. Both sides knew that the Germans were still, even as their empire fell, producing designs and weapons that were far in advance of what the allies could dream up.
If telephones are outlawed, then only outlaws will have telephones.
It's a simply ploy on misdirection. It's been around in one form or another for years. Back in grade school, we had word problems that played on this where we had to select the proper information to solve a math problem.
It can be done/demonstrated easier with coins and not harming any animals. Assemble 3 coins (US currency) a penny, a nickle, and a quarter.
Now tell them that Johny's mom had three kids. Point to the penny and say the name Penny, point to the nickle and say the name Nicolas, then point to the Quarter and ask what the third one's name is. Most people will spend a considerable time attempting to work quarter or some variation of it into a name even after repeating that Johny's mom had three kids. Eventually they give up.
(in case anyone is wondering, the third one's name if Johny- as in Johny's mom). It's a little easier then how far can a dog run into the woods.
Damm if I know. The account was written by one of guys doing the breaking in, not by one of the analysts.
I read somewhere (maybe Max Hasting's book on Winston's War) about a problem the British had with some infantry equipment getting wet and non-functional. They supposedly solved it by going to condom makers, who made a several foot long condom to fit over the gear and keep it dry.
When Churchill saw this, he said that it wouldn't do at all - he wanted each pack labeled "British Condom. Size - Medium."
You were probably joking when you posted, but there is a chess variant that looks interesting:
http://www.chessvariants.org/incinf.dir/kriegspiel.html
putting the 'B' in LGBTQ+
I like how the wikipedia article specifies that this math problem is known as the German Tank Problem in the *English-speaking* world. Apparently, the math worked.
Ceci n'est pas un sig.
If you want a unique random number, just pick a random number and make sure it hasn't been used before. GUIDs aren't magical; they're actually less unique than the simple method I just described. Too many people used GUIDs for poor reasons.
Besides, if you used traditional GUIDs, you would not only be exposing when the tank was made, but also where it was made.
The details are trivial and useless; The reasons, as always, purely human ones.