## FBI NEWS / decryption

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Kromix
Posts: 288
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Location: DFW, Great State of Texas

### FBI NEWS / decryption

Thought about posting it in news, nut why not in logic puzzles as this is the likely forum for people who love to decrypt messages

Found this piece today: http://www.networkworld.com/community/b ... pted-notes

With these notes that need decrypting http://www.fbi.gov/news/stories/2011/ma ... ge/gallery

Why not give it a shot to help out in some way, lol.

Images Spoilered

Spoiler:

Spoiler:

Click Me! <---- Click There!
Spoiler:

Inglonias
Posts: 126
Joined: Mon Jun 28, 2010 5:54 pm UTC

### Re: FBI NEWS / decryption

First note has the word "pi" in the upper right hand corner.

I'm no cryptographer, but it may mean something. Possibly some sort of key? Pi would certainly make a good key. Plenty of numbers to choose from...

EDIT: That actually may be "PL" upon closer inspection.

jaap
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### Re: FBI NEWS / decryption

Inglonias wrote:That actually may be "PL" upon closer inspection.

Or just p1, i.e. page 1.
Last edited by jaap on Fri Apr 01, 2011 1:40 am UTC, edited 1 time in total.

Inglonias
Posts: 126
Joined: Mon Jun 28, 2010 5:54 pm UTC

### Re: FBI NEWS / decryption

Possible. I don't think we're thinking of anything new here. If the FBI told the internet what they've already tried, we could help them.

There's discussion on the Escapist that these are parts of a one-time pad. If that's the case, then there's very little we can do.

Moose Hole
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Joined: Fri Jul 09, 2010 1:34 pm UTC

### Re: FBI NEWS / decryption

The first one is a grocery list. He wants eggs, milk, and york peppermint patties. I have no idea about the second one though.

undecim
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### Re: FBI NEWS / decryption

Inglonias wrote:Possible. I don't think we're thinking of anything new here. If the FBI told the series of tubes (old joke is old) what they've already tried, we could help them.

Thor's discussion on the Escapist that these are parts of a one-time pad. If that's the case, then Thor's very little we can do.

If it were a OTP, then the‎re would not be so many repeated letter patterns.
Blue, blue, blue

Moose Hole
Posts: 398
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### Re: FBI NEWS / decryption

undecim wrote:
Inglonias wrote:Possible. I don't think we're thinking of anything new here. If the FBI told the series of tubes (old joke is old) what they've already tried, we could help them.

Thor's discussion on the Escapist that these are parts of a one-time pad. If that's the case, then Thor's very little we can do.

If it were a OTP, then the‎re would not be so many repeated letter patterns.
True. But what if groups of letters are keys to the pad rather than individual letters? If that were the case, i don't think the patterns of numbers would be in the same place.

I think this is more of an organically created code rather than something a cryptologist would come up with, because he is supposed to have been doing it since he was a kid. The letters might mean something phonetically, or they may each mean something in whatever context this paper was being used for, like N for nice or P for purple.

Corka
Posts: 17
Joined: Wed Sep 15, 2010 2:16 am UTC

### Re: FBI NEWS / decryption

A couple of things to note. Every open bracket has an appropriate closing bracket. This would indicate they have a specific meaning, rather than having their values picked by a polyalphabetical cipher. The use of brackets is heavy in the first note but lacking in the second note. The brackets are also never nested. The space between them is sometimes too short for them to be deliminating individual sentences, and they are not used very much in the second note. It is possible that they represent quotations. They could actually be used to mark regions which are using different cipher keys whether they be monoalphabetic or polyalphabetic and that would make looking at the frequency of letters a bit more difficult, but I don't think that is the case because we do actually see repeated patterns across brackets.

This is not merely a transposition cipher. If it were, we would see a much higher occurrence of the different vowels. The only one that has frequent occurrence is the letter E. That doesn't rule out the possibility of it being a combined transposition and caeser cipher.

We can see certain repeated patterns. In particular many of these words seem to end in the letter E, and we have some repeated patterns.
If you look at the lines on the bottom note, we see:
71NCBE
74NCBE
WLDNCBE
WLDSNCBE

and similar patterns occur earlier in the same note. WLDNCBE appears on lines 5 and 6. WLDNCBE also occurs on the third line of the second note.

We can see other patterns which have a similar form to them. ERTE, FRTSE, NARSE, PSESHLE, VLSE, MTSE, CTSE, GLSE, all of these appear at the end of a word of sentence, and such forms do not appear to be at the beginning. The beginning of the words seem to have less recurring patterns, but there still are a few. In particular, a lot of them are prefixed by TF, TE, or AL.

Looking at this I think this isn't a transposition cipher, polyalphabetical cipher, or monoalphabetic cipher. But because of this repetition I think he is nonetheless using a similar ciphering technique. It is possible that he is actually ciphering entire regions, for instance replacing something like TION with NCBE, but not by matching the individual letters. He doesn't need to match letters, or have these regions the same length as those he is replacing. When he comes across a new word ending, he just modifies one of his existing endings slightly and adds it to his list. As such, WLDNCBE and WLDSNCBE might actually translate to very different things. Or he could be doing this syllable by syllable, in which case those two actually do translate to highly similar words. He could be performing this on written english words, but potentially also based on the phonetics. He could even be basing this on a different language if he knows one other than English.

Thoughts?

Corka
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Joined: Wed Sep 15, 2010 2:16 am UTC

### Re: FBI NEWS / decryption

You know what? I was an idiot for assuming that I was actually putting forward anything constructive. This could just as easily be some short hand filled with acrnoyms that he uses, or a list of serial or manufacture codes. What did he do for a living anyway? It could be work related notes.

Ddanndt
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Location: Paris

### Re: FBI NEWS / decryption

When I first looked at the code, I couldn't stop think about a scrabble letter-point cipher but I don't think it's it. But I still find it weird that the FBI were unable to unravel a code made by a simpleton. And they could have given more clues about the guy (e.g where he lives, his occupation, hobbies etc ...)

Spoiler:
NCBE = AMMO
God does not care about our mathematical difficulties — He integrates empirically.
—Albert Einstein