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Notes on Kryptos Part 4

Copy of message I sent to the Kryptos group on Yahoo! for anyone whose working on Kryptos but not in that group.

Given Elonka's notes mentioning that K4 uses a cipher system not known to anyone else I decided to investigate other possible ways of attacking K4. Specifically, I wondered if the BERLIN crib might not be as simple as NYVTT turning letter for letter into BERLIN.

First I assume that this is something that's breakable by hand as was the rest of Kryptos and thus would simply be based on MOD 26 arithmetic of letters and might involve transposition of characters.

So I went to see if there's a word that could be permuted to create some permutation of BERLIN from NYVTT. There is: it is SILENT


More strikingly this works if you are sliding SILENT from the start of K4, it falls in just the right position to make BERLIN


Now leading on from this I wonder if the cipher used for K4 consists of permutations of both the key and the ciphertext. Note how BERLIN is permuted within itself and so then I returned to the start of cipher text to see if there's a permutation of SILENT that results in a word (after permutation) starting in position 0. Once again there is:


i.e. the word is WOMEN, assuming that the G is in the word after women. In this case ILENTS is a simple rotate of the word SILENT (just as ENTSIL followed by ENTSIL gives us BERLIN). There are likely other words as well, but this one is strikingly long.

Running through all six possible rotations of SILENT you get:







If you look you'll see various words popping out (in the ILENTS set, second row above, there's WOMEN at the beginning and closer to the end an anagram of WATCH).

Perhaps there's a method to choosing which shift of SILENT to use followed by some sort of transposition.


Unknown said…
Mod26 is such a great concept for K4 given all of our difficulty in solving it. Unfortunately unless the linear arrangement of the K4 text was changed and then enciphered, we would want to see the decryption reveal the word BERLIN in order in that position exactly to be sure one was on track. You've inspired me to revisit the Hill cipher especially since I'd been feeling stuck in a rut so, thanks! -Kfan
Unknown said…
Key the Roman Numerals from the CIA wall against K4. Add QIX:



Unknown said…
what if we are looking at this from the wrong angle. like if it is corner to corner bottom left to top right but in reverse order
Unknown said…
what if we are looking at this from the wrong angle. like if it is corner to corner bottom left to top right but in reverse order

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