I do not remember very well the theory, but one of the hardest part of the kasiski analysis was to discover which was the key length; and the fact is that you can only discover it, if the length of the cipher text is longer enough and the key shorter enough (we'll need practice to know this). isn't it?

Anyway, in those years, neither computer (i do not include the mechanic machine for calculations made by Babage) nor high level programming languages exists. Now, we can break that code by brute force (the only important thing, is to know if the ciphertext is a polialphabetic cipher or not) for discovering the key length with the frequency analysis help ... a'm i wrong?

I think i must read those old books of cryptography to analyse with great appetite your code ... but i'm curious and i cannot wait, did you use brute force, or another intersting algorithm for breaking the vigenere cipher? I mean, on your last post, you said that you've been written a extrange method to break the vigenere cipher.

Saludos :-)


PS: umm, i've made a code breaker script for the scitale cipher ... but it have some problems with thick scitales ^_^> ... i hope to submit it later, when i have some spare time. cheers

PS2: i forgot to say, great work! (i didn't know Babage break the Vigenere cipher before than Kasiski did)

perl -Te 'print map { chr((ord)-((10,20,2,7)[$i++])) } split //,"turo"'

In reply to Re: Breaking the indecipherable cipher, courtesy Charles Babbage. by turo
in thread Breaking the indecipherable cipher, courtesy Charles Babbage. by chargrill

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