7.0148 Qs: Caesarian Ciphers (1/41)

Wed, 1 Sep 1993 11:02:56 EDT

Humanist Discussion Group, Vol. 7, No. 0148. Wednesday, 1 Sep 1993.

Date: Tue, 31 Aug 93 19:15:54 CDT
From: stan kulikowski ii <STANKULI@UWF>
Subject: caesarian ciphers

in suetonius somewhere there is a famous passage describing the ciphers
that julius caesar and augustus used. this is often cited in crypto texts
as the earliest examples of encryption, using monoalphabetic substitution.
i once read an english translation of this passage, and as i recall it
said that julius advanced the alphabet by 3 letters (so 'A' became 'D'),
and augustus advanced it only 1 letter when writing in cipher. i assume
that last letter in the alphabet wrapped around to the start of the
sequence; and punctuation, word spacing and any digits were either
nonexistent in text at the time, or were copied plaintext into the cipher.

i am currently teaching a computer networking to some military
cryptographers, and i would appreciate some scholarly assistance if anyone
here is familiar with this text.

i would appreciate a reference to the suetonius citation (i have lost
mine to the english translation). indeed, if someone could copy the
latin passage to here, i would be grateful. i do not think it was very long.

i am assuming that at the time of julius and augustus there were 22-24
letters in their latin alphabet. i seem to recall hearing that claudius
tried to add a couple letters to update their phonics, but for some reason
scholars did accept these innovations. could someone provide me with the
alphabetic order that the suetonian ciphers were operated upon?

how accurate is this claim of suetonius that the early caesars actually
used these ciphers? is there any existent text which is thus encrypted?
by this i mean, ancient documents (of any age) which used these ciphers.
was this a common practice in the middle ages and how many such still exist?
i understand that there are documents (do i remember 'the voynich
manuscript'?) which remain today undeciphered.

my thanks for this help.

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god created space so everything would not happen to me
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