[EXT] Re: Help with OTP encryption

[Zdenek Wagner]

OK. As another interesting point, Vernam cipher is the only one which
was mathematically proved as unbreakable if the keytext is used only
once. During the cold war large puch tapes with random keytexts were
delivered as a diplomatic mail and the encoding/decoding machines
physically destroyed the bytes which were just used.

Zdeněk Wagner
http://ttsm.icpf.cas.cz/team/wagner.shtml
http://icebearsoft.euweb.cz

st 19. 5. 2021 v 16:07 odesílatel Jonathan Fine <jfine2358 at gmail.com> napsal:
>
> Thank you Zdenek for this contribution
>
>> if I understand your original mail, what you need is a slight
>> modification of Vernam cipher. Modules for Vernam cipher should be
>> available in many programming languages.
>
>
> It led me to https://en.wikipedia.org/wiki/Gilbert_Vernam, and how an operator mistake allowed https://en.wikipedia.org/wiki/Cryptanalysis_of_the_Lorenz_cipher.
>
> So thank you not only for answering the original poster's question, but also bringing this thread to a close (I hope) with an interesting piece of information.
>
> --
> Jonathan