I from a crypto history book I read in high school: in WWI, German intercepts of Russian transmissions have the Russians illusions of German tactical genius. Somehow, Germans would often be in position to confound the Russians. The reason for this: Russian code clerks were badly trained. Sometimes there would be a couple of attempts to send a message followed by a plain-text transmission by the frustrated code clerk. This was a tremendous boon to German cryptographers in the long term as well as a giveaway of tactical maneuvers in the short term.
In WWII, the Germans had their turn at incompetence. Enigma machines were supposed to be "warmed up" by 3 random characters. The purpose of this is like an Initial Vector or a "nonce" in modern block cipher use -- a bit of entropy to help obscure often almost identical message headers. A lot of German code clerks were lazy and just typed in "AAA", which helped out the Bletchley Park cryptographers a lot.
Modern crypto technology is often very good, but only if used correctly. Security fails most often because of human error. (This includes programmers!)
While we're telling war stories. ;) Nonces played a role in a major American blunder too.
During the Battle of Leyte Gulf, Admiral Halsey moved his massive Third fleet out of position to chase a Japanese ruse. The Japanese then moved their Central Force through the gap and attacked the much smaller and ill-prepared Seventh Fleet.
The commander of the Seventh Fleet sent several desperate messages asking for Halsey's help, causing Admiral Nimitz at Pearl Harbor to send a message to Halsey asking, simply "WHERE IS TASK FORCE THIRTY FOUR?" (Task Force 34 was the Third Fleet's detachment of battleships).
His clerk changed the message to WHERE IS RPT WHERE IS TASK FORCE THIRTY FOUR? And then, while forming the message, added the beginning nonce "TURKEY TROTS TO WATER GG" and the trailing nonce "RR THE WORLD WONDERS". The "GG" and "RR" were indicators of the end and beginning of the nonces.
Halsey's clerk removed the first nonce, but left the last one "THE WORLD WONDERS" as part of the message, apparently missing the "RR". So when Halsey got the message, it read "WHERE IS RPT WHERE IS TASK FORCE THIRTY FOUR THE WORLD WONDERS".
Halsey interpreted the message as sarcastic criticism of his decisions by a commanding officer over official channels, and flew into a rage. He then decided to delay the Third Fleet's assistance of the Seventh Fleet, ostensibly to refuel his destroyers.
Had he sent the battleships immediately, they likely would have crossed the Central Force's T and crushed them. It would have been one of the greatest (and last) battleship duels in history.
Of course the blunder didn't affect the outcome of the war, or even the battle in a strategic since. The Seventh Fleet was able to turn the Central Force back, mostly through self-sacrificial courage on the part of the destroyer crews.
the Third Fleet was able to turn the Central Fleet back on their own mostly through self-sacrificial courage on the part of the destroyers.
I know of that action from documentaries. Basically, the destroyers engaged heavier ship classes which they theoretically had no hope against. In some cases, "charged" is actually more apt than "engaged."
All crypto systems fail when faced with human operators!
There was one story of an Afrika corp operator who sent HIT - LER as the 2 'secret' triplets every day for the entire North Africa campaign. Then disastrously he was captured!
It's an interesting question as to whether at least the best (4-wheel naval) system could be cracked without operator error or deliberate plain text seeding.
The only flaw of the enigma is that a letter cannot be encrypted to itself - I have heard different accounts of if this was enough to always make it crackable.
It's an interesting bit of military psychology that while every side in WWII broke their enemy's codes - all of them believed all their own codes to be unbreakable!
It wasn't a nonce as such - it was a key exchange, slightly more like a salt in modern terms.
One of the main failings of the Germans was their love of formal introductions and sign offs in official messages, especially by the navy which otherwise had rather better crypto than the other branches. However if you are already stuck with a language that has a very fixed word and sentence structure you don't help by signing all your messages with the same 40 character long formal greeting.
It wasn't a nonce as such - it was a key exchange, slightly more like a salt in modern terms.
The way we think about ciphers has almost completely changed with the advent of cheap computation. Also, I read that book in High School and haven't thought much about Enigma in about 16 years, so it's entirely possible I got that a bit wrong.
However if you are already stuck with a language that has a very fixed word and sentence structure you don't help by signing all your messages with the same 40 character long formal greeting.
So, if you want to keep secrets, it doesn't pay to have a stick up your...
Another way to put it: it pays to be more like Snoop Dogg and less like Colonel Klink.
A really great book [1] which details how Marian Rejewski, Jerzy Rozycki and Henryk Zygalski exploited a lot of these human errors and managed to keep up with the changes of the Enigma machine.
which is outside the NSA headquarters. They have old Enigma machines, which are quite compact, about typewriter size, as well as a decoder, which is more like a bank of refrigerators. And a lot of other artifacts. It seemed to be mainly a labor of love by retirees and crypto geeks, rather than some officially compiled museum. Rather touching, in a surprising way.
In WWII, the Germans had their turn at incompetence. Enigma machines were supposed to be "warmed up" by 3 random characters. The purpose of this is like an Initial Vector or a "nonce" in modern block cipher use -- a bit of entropy to help obscure often almost identical message headers. A lot of German code clerks were lazy and just typed in "AAA", which helped out the Bletchley Park cryptographers a lot.
Modern crypto technology is often very good, but only if used correctly. Security fails most often because of human error. (This includes programmers!)