A 1941 Paper-and-Pencil Cipher

Schneier's blog links to a photo of a 68-year-old code being employed in wartime, with a plausible explanation of what is going on in it. (The photo is from the Life Magazine archive we discussed when it went live.) "What you see here is a photo that never should have been allowed to be taken, and one which provides an amazing, one-of-a-kind glimpse into the world of WWII espionage and counter-espionage. As far as I can tell, what is shown in this picture is an FBI agent in New York encrypting a message, passed from 'DUNN'... through Sebold, prior to transmitting that message to Germany via shortwave radio. ... [T]his appears to be real cryptology at work."

Comments

Duh?

[east coast]

Why didn't he just use a computer for this? I swear, those people were so dense.

Re:Duh?

[bobdotorg]

Why didn't he just use a computer for this? I swear, those people were so dense.

They weren't dense, Windows DE (Depression Edition) kept crashing that day with repeated PCODs (Punch Cards of Death).

Though now that I think about it, I've come to the realization that every version of Windows is Windows DE.

Re:Duh?

[Anonymous Coward]

Actually, back then he probably was the "computer."

It had a definition before we invented the machines.

Re:Duh?

[corsec67]

Punch Cards of Death

Would that be a IBM Doily?

Re:Duh?

[VagaStorm]

Oh, indeed, http://en.wikipedia.org/wiki/Human_computer, they even did parallel computing :)

Re:Duh?

[timeOday]

Why didn't he just use a computer for this?

Actually he was a computer - that's what they called people who did mundane computations before machines took over their job.

Re:Duh?

[Sanat]

Back in the day of card punches in order to certify that a card punch was working properly a whole box (qty 2000) cards were fed, punched and read with only one error permitted. This was CDC equipment on the CDC 3100 and 3200 models.

If something was not quite adjusted properly usually a failure would occur much earlier in the cycle.

Sending out a new operating system was done with punch cards. A simple bootstrap program was keyed into the core and executed which would input from the card reader and a whole box of cards needed to be read without error.

The CDC card punch (can not remember the model number ... maybe 3114) also had a read station in it so that a read after write cycle could be employed. The error exit could be used to offset the card in the output deck about 1/4 of an inch so that the individual card could be easily located and re-punched.

Reading a lace card was a real dicey test. Usually we alternated rows and columns.

PCOD sounds about right.

Human computers

[El Lobo]

More than 13 000 special trained persons worked with encryption/decryption related tasks in WWII (and that's allies only). Yes, there were no computers then the way we know them now, but 13 000 people working shifts day and night was a significant force as well.

Re:Human computers

[Linker3000]

Wow - imagine if those people clustered around someone reading Beowulf!

Re:Human computers

[memristance]

Of course, some methods were better than others...

Re:Human computers

[lysergic.acid]

speaking of which, here's a screen shot of an early pre alpha build of the Folding@Home client.

Double bluff

[adamwright]

We may consider, however, that the people allowing the photograph to be taken may not have been *entirely* honest when setting up the contents and cryptographic "method" being demonstrated.

Re:Double bluff

[devnullkac]

There is another picture with the same message apparently being approved by Hoover. It also shows most of the text so carefully covered up in the photo in TFA. Part of it is in shadow and perhaps someone more skilled than I with GIMP can tease it out (frankly, I think you'll need access to the photographic negative), but "... the following message to:" is what's visible. This lends credence to the "setup" theory, since that's hardly worth covering up for a photo op and even if it were, why be so careless as to reveal it in another photo (on J. Edgar Hoover's desk, no less).

Re:Double bluff

[mlwmohawk]

You are working on the assumption that what you see is an authentic photo of someone actually working.

If you have any professional experience at all, you'd know that pictures are NEVER taken of actual work. The photos are always staged to look good.

Be it a technician posing in front of the product with tools, an engineer posing in front of an oscilloscope with an interesting wave form displayed, another engineer in front of a very neat and orderly (but complex looking) white-board, and so on. Every company in which I've worked, the arrival of a photographer is carefully orchestrated.

All pictures have a perspective and something that the photographer's employer wishes to convey. It is very likely that the picture is a standard professional photo that shows "what it looks like" without showing actual work. The words chosen carefully to spark interest in the subject by those who view it. Like now.

Re:Double bluff

[argent]

You are working on the assumption that what you see is an authentic photo of someone actually working.

It doesn't matter whether it was staged or not, it only matters that it contained code words relevant to what we now know was an active intelligence operation at that time it was taken.

Re:Double bluff

[Anonymous Coward]

Of course the words are relevant to what we know, we know the information we are allowed to know.

You're just being a jackass. His point is that if the information was such that the Germans could have deduced that they were being double-crossed then it makes no difference in the world if it were staged or not. It's still a blunder.

Re:Double bluff

[westlake]

If you have any professional experience at all, you'd know that pictures are NEVER taken of actual work. The photos are always staged to look good.

LIFE's photo essays were always scripted before production.

The editors knew the story they wanted to tell and the photographer would be sent out to capture it on film.

He might resent the constraints.

But his logistical and technical problems are mostly solved. People know he is coming, all his ducks are in a row.

He should have no problems making his deadline and if the schedule isn't realistic or he hasn't received the proper clearances, he has the editors to blame.

Consider the lighting and composition in these photographs.

These are not candid shots.

The photograph in the archives is not, of course, the photograph in print. There would have been a dramatic loss of detail.

Re:Double bluff

[Z00L00K]

It is possible that this was a partial setup, but in this case it was the question of a deception message that was about to be sent using encryption that was probably already blown at the time.

And mind that the encryption wasn't US encryption, but German encryption so if the encryption was blown and the agent was already cold then it may have been a semi-arranged situation where it was real life data that already had cooled that was used.

And the whole setup could have been intentional from the intelligence point of view because in some cases you may want to double-deceive the counterpart. This means that the counterpart may have to think that they got false data, but the data was actually real, and then it was necessary to seed confusion. Be aware that this message may not be the message intended to be the one they wanted to obscure but another much more sensitive. Because if you reveal that you know of something then a lot of the earlier messages also will be cast in doubt.

So the question why this photo was taken may be revealed in another message, but we may never see an answer to that.

Espionage and counter-intelligence is never straight, it's full of deception and double-deception.

This actually leads to a story (I can't confirm it, but someone else may) that an intelligence officer with knowledge about the D-day landing sites was captured in France and when the Germans questioned him he did give them the correct info straight on, but they didn't trust that so after some torture he instead claimed that the beaches around Calais was the landing site.

Re:what's the big deal?

[Tumbleweed]

I don't see what the big deal is. You guys have never seen someone doing a word search puzzle before?

And the answer to today's word jumble is: "NORMANDY"

Re:what's the big deal?

[Alpha Whisky]

Like this? http://www.historic-uk.com/HistoryUK/England-History/Crossword.htm

Cryptography vs Cryptology

[Doc Ruby]

What is at work there is cryptography , not just "cryptology. It's actually the generation of encoded symbols, not just any practice connected to the study of hiding information.

July 1940 != prewar

[Anonymous Coward]

Just because America was neutral doesn't mean the war hadn't started.

Re:July 1940 != prewar

[IvyKing]

Since the US did not declare war on Japan until December 8, 1941 (and Germany on December 11, 1941) July 1940 is legitimately pre-war as far as the US is concerned. BTW, the first US casualties from WW2 took place in China in 1937.

Re:July 1940 != prewar

[lysergic.acid]

according to the comments FTA, the phrase "pre-war German espionage code" is referring to the age of the encryption algorithm being used, not when it was used in the photo:

Thiago: It's not meant to be Americentric: Duquesne entered German service in February 1939, and I'm willing to bet that the cipher in question dates back earlier than that, based on what I know of wartime crypto history. As I recall, at the time (1939-1941) the high-level military and diplomatic traffic was encrypted with Enigma machines, and everything else used codes that dated back to the early 1930s, or before (and were fairly easily broken by, e.g., Bletchley Park.)

Hence, "pre-war", as opposed to a later, military, war-time code.

Re:July 1940 != prewar

[vux984]

Since the US did not declare war on Japan until December 8, 1941 (and Germany on December 11, 1941) July 1940 is legitimately pre-war as far as the US is concerned.

er... By that logic since Switzerland did not declare war at all, July 1940 is legitimately 'prewar' for them too? Of course, so is November 2008... in fact as far was the Swiss are concerned there was no war?

Are we still 'legitimately pre-World War II as far as the Swiss are concerned'?

Any Swiss care to weigh in on this absurdity? ;)

Re:July 1940 != prewar

[vux984]

Since Switzerland didn't declare war, "pre-war" is a non-sequitor for them.

Not at all. Just because a country wasn't in the war, that doesn't mean they don't acknowledge that it existed, that it started or that it ended. Switzerland can talk about what it was doing pre-WW2, post-WW2, and during WW2 without it being a non-sequitor.

I agree with the Chinese viewpoint that WW2 started in 1931...

The date the world has agreed a war started is pretty arbitrary in almost ANY war, but it serves as useful frame of reference, and its not generally useful not use the 'agreed date'.

Schneier's post

[bobbozzo]

Since tfa didn't link to Schneier's blog, here it is:
http://www.schneier.com/blog/archives/2008/11/1941_pencil-and.html

Re:Schneier's post

[elgatozorbas]

Imagine a Beowulf cluster of these...

Oh wait, it's called college.

The cipher

[Anonymous Coward]

from comments under the article (for those who don't read comments except on slashdot):
It looks to be just a transposition cypher. The "key" is the arrangement of columns from 1-18. You write the message down with 18 columns across, then read down each column in the order given by the key, grouping in 5s. I suspect the caption is actually correct ... you wouldn't need such a complicated worksheet and all those typed strips for encryption, but they would make it easier to get the columns lined up when decrypting, so I imagine the cryptographer is decrypting the message to make sure it was encrypted correctly before sending it.

Wait, I thought...

[WED Fan]

Actually he was a computer - that's what they called people...

I'm confused, I thought...

Soylent Green == People

Computers == People

Soylent Green is edible.

People are edible.

Question: Will be Dell laptop work with a South Beach diet?