> Enigma is interesting because it's so famous and yet it's completely the wrong design, The allies sigaba was basically the same design-- but it lacked the re

> Enigma is interesting because it's so famous and yet it's completely the wrong design, The allies sigaba was basically the same design-- but it lacked the reflector so letters could encrypt to themselves. The down side of this is that it needed a complex mechanism to reverse the signal flow when switching between encrypting and decrypting. (there were many other improvements in sigaba, but the big one that made it hard to crack was eliminating that one weakness) > You could perhaps say Lorenz is a (distant) ancestor of, say, ChaCha20. The first cracked Lorenz message happened because a signal re-transmission was needed so they sent the same message again using the same keystream-- except it wasn't the same message: the operator abbreviated a word, shifting the following characters. So they effectively reused the same keystream with different messages. Systems using stream ciphers (e.g. CTR mode) are still falling to this today. Seems we haven't learned that much after all!