Help Break Original Enigma Messages

Stereo writes "The Enigma Machine was cracked in Poland in 1932, but three messages remain unbroken, despite having been intercepted in the North Atlantic in 1942. The M4 Project, named after the four rotor Enigma M4 used for encryption, is a distributed computing effort to break them. One message has already been deciphered successfully!"

Comments

Re:Error

[Anonymous Coward]

One of the main reasons the Enigma crypts were breakable with 1940's technology is that the Germans did _not_ do useful things like that. They re-used keys, left cribs in the messages, etc.

Basically, they put too much faith in the encryption technology, and didn't put enough effort into securing the rest of the process. It's not unusual, many of today's systems have similar issues.

The comments in Bruce Schneier's blog list some more things that went wrong in the Enigma process.

Enigma is fundamentally flawed.

[Convergence]

Enigma has a fatal flaw: No letter could be encyphered to itself. This is an artifact of the 'reflector disc' at the end this means that a known plaintext, or crib, can be ruled out for a particular offset, if any letter of it matches a letter in the cyphertext. This, combined with message statistics, allows for powerful cryptographic techniques to be used. These techniques were unavailable in WW2, but they exploit fundamental weaknesses in the design.

Of course, in WW2, it was the misuse of enigma that made it particularily easy to break --- It might only take one weather report to learn the daily subkey. Had Enigma been properly used, it would probably have been nearly unbreakable with WW2 era technology.