davidjackson > 15-06-2017, 09:53 PM
Vonologia > 15-06-2017, 11:48 PM
(15-06-2017, 09:53 PM)davidjackson Wrote: You are not allowed to view links. Register or Login to view.I spent a summer once making volvelles out of the VM. It was fun but eventually fruitless work.Only if there was a direct glyph to glyph translation? If one glyph meant two or three or five, would frequency distribution still apply? Also, apologies for not differentiating between "code" and "cipher." Meant one in the same, but in the field of cryptography, they are different.
Actually, I couldn't be bothered before to go into this, but since the topic has risen its head again I may as well.
It is quite easy to prove that the VM is not the product of an Alberti cipher ( or other polyalphabetic cipher).
In essence, this is because such ciphers create pseudo random cover text - they mask the frequency distribution of the plaintext.
But the VM corpus doesn't exhibit that characteristic. Quite the opposite. Instead, glyphs are highly positionally aware within vords.
Ergo, it is not the result of an Alberti cipher. Or if it were, it would quickly succumb to frequency analysis, which it doesn't.
davidjackson > 16-06-2017, 06:00 AM
Davidsch > 16-06-2017, 12:55 PM
(15-06-2017, 09:53 PM)davidjackson Wrote: You are not allowed to view links. Register or Login to view....
It is quite easy to prove that the VM is not the product of an Alberti cipher ( or other polyalphabetic cipher).
In essence, this is because such ciphers create pseudo random cover text - they mask the frequency distribution of the plaintext.
But the VM corpus doesn't exhibit that characteristic. Quite the opposite. Instead, glyphs are highly positionally aware within vords.
..
Vonologia > 16-06-2017, 03:16 PM
(16-06-2017, 06:00 AM)davidjackson Wrote: You are not allowed to view links. Register or Login to view.A polyalphabetic cipher encodes one to many. So plaintext A could be encoded as b,j,l or m. For example.
Hence, frequency distribution is pseudorandom in the cover text, and no, frequency distribution would not apply.
The VM almost -but not really- acts as if it were a simple Caeser cipher, because at first glance you could almost assume there was a glyph to glyph correspondence. Because glyphs are positionally aware. But when you examine the text, it doesn't yield to any known language. And with the corpus that we have, someone would have spotted something by now.
Have a quick search for Visconti, The subject has been mentioned a few times. Or start a new thread if you have a new angle.
R. Sale > 16-06-2017, 07:14 PM
davidjackson > 16-06-2017, 09:45 PM
Quote:Alberti cipher using codephrase "elephant":
the sun was very hot today becomes SFAQU LCQVB QYBMS RKAEY
"t" can be "s" or "r"; "h" can be "f" or "b"; etc.
There is no frequency distribution.
Quote:Caser shift -2:
the sun was very hot today becomes rfc qsl uyq tcpw fmr rmbyw
And we can see that "t" is always "r"; "h" is always "f"; "e" is always "c", etc. The frequency distribution of the letters is identical (r appears the same numbers of times as t, h as f, etc).
Quote:But if there is a code/cipher, it could be more complex or related to and better technology than an Alberti cipher. Yes?
Koen G > 16-06-2017, 11:32 PM
Vonologia > 16-06-2017, 11:47 PM
(16-06-2017, 11:32 PM)Koen Gh. Wrote: You are not allowed to view links. Register or Login to view.Keep in mind that all pre-modern ciphertexts are several orders of magnitude smaller than the VM. The large ones are the length of a note, a paragraph....
The VM is an entire MS, hundreds of pages. The more complex your proposed cipher becomes, the less likely it has been used to encode and decode this text.
Additionally, there are indications that the VM is similar to manuscripts that were carried around by professionals. Quick reference stuff, not desk-cipherdisk-takes-two-hours-to-read-a-sentence stuff...
-JKP- > 16-06-2017, 11:57 PM
(16-06-2017, 11:47 PM)Vonologia Wrote: You are not allowed to view links. Register or Login to view.What if each "paragraph" is it's own entire encoded message and the VMS is just a collection of messages over time?
Smaller, harder to crack, and each unique.