Introduction and question

[Knozzmoeking]

Thanks for approving my membership here. I've followed this case on the periphery for years and have done quite a bit of reading here and elsewhere.
I don't have a pet POI and my opinions on key parts of this case have swung back and forth over the years.

Since my post is an intro and a question about the ciphers, I figured I would post it here.

I'm headed down a logical (to me) road with my thoughts on the 340 and its possible solution. I'm a negative one on the scale of 1 to 10 when it comes to the technical aspects of cryptography so my appeal is to anyone with any level of understanding or expertise.

My question is this - "How complicated is the 340 cipher compared to the 408 cipher?"

To maybe make it a little clearer where I am going with this question, in math the equation 1+1=2 is light years away in complication from e=mc squared (sorry - can't find the superscript).
Are the 408 and 340 ciphers that far apart?

[Tahoe27]

Welcome aboard. I'm no pro, but I'd say "yes". Once you see how the 408 was done, you realize how basic it is. I guess until when (and if) we see how the 340 was comprised, we don't really know, but we see all the work done so far....and no such comparison can be made. It's certainly far from the easy make-up of the 408.

[traveller1st]

Welcome and thanks for the intro.

Also .... what Tahoe said.

[doranchak]

My opinion is that if the 340 was made in the same way the 408 was made, it would likely be solved by now. It's long enough to give us a lot of statistical clues to help us break it.

But there's something different about the 340. We don't know yet if that difference is simple or complicated. Or even if there is a real message behind it.

It could be a complicated difference, such as going through a whole bunch of steps to further hide the message before applying the symbols.

Or it could be a simple rule, like "every time you see a plus symbol, reverse the direction of the message."

Many simple rules like that are possible. They are limited only by our imaginations. The complicated thing is to search through all the possibilities to figure out which ones should get a closer look.

[Knozzmoeking]

Thanks for all of the quick replies.

First let me say that I have run across similar thoughts to the ones that I have in my head right now as I read through this site. I am not intentionally lifting anyone's ideas.

My thought pattern goes like this. If I read posts about the ciphers correctly, the 408 was relatively simple. It was solved relatively quickly. Let's call this Cryptology 101.
For the next cipher, did Z suddenly move to a PHD level cryptology ability or did he retain his rudimentary 101 skills and do something very basic to disguise that he hadn't turned into a PHD overnight? For example, I read in one thread speculation of an obvious break in the 340 between lines 9 and 10 or 10 and 11 (sorry about the lack of a link). Is it possible that Z did something as simple as folding this cipher along a certain row or column thus rearranging the cipher while retaining the same solving methodology as the 408?

I realize from reading this site that what I am asking is very simplistic (bordering on naïve). I just have a suspicion that Z was not that advanced as a cryptographer and "out of the box" directions may yield results.

[doranchak]

A simple fold could have been done but I think others have tried to attack the cipher with many variations of that idea, still with no success. It could just be that the right combination of "folds" has not yet been tried.

The papers reported that Donald Harden thought Zodiac was unsophisticated, and possibly borrowed his idea for the 408 from a "not too high level detective story".

It's easy to suppose that Zodiac read those reports and decided, "I'll show them!" My guess is he came up with some weird step on his own for the 340. Many kinds of classical cipher types are well understood and studied, but "weird step" or homemade ciphers seem to be poorly understood. A good example is the encrypted notebooks of the Unabomber, made using a LOT of weird steps, which no one figured out until the FBI discovered the decipherment instructions in his cabin. How can such rules be discovered using traditional cryptanalysis? That could be what we're facing with the 340.

[Tahoe27]

I think too, this is why many have thought the "key" lies somewhere in one of his other mailings. I think it's obvious by now we cannot decipher it without one. I could be wrong--doranchak is certainly more qualified than I, to say.

I have often thought about the Bus Bomb letter since it was mailed (pretty much) along with the Dripping Pen card. The timing of it all anyway!

[doranchak]

Yes, we either have to discover his key somewhere, or get lucky and identify the cipher type AND run a successful attack that can find the right key.

The timing is interesting. Maybe the 340's message also mentions things he wrote about in the bus bomb letter, and/or refers to his recent killing of Paul Stine.

[WoodenIgloo]

Hi Dave,

Please evaluate this proposed solution.

http://www.zodiacciphers.com/zodiac-new ... -john-rose

Thank you very much!!!

Wood

[doranchak]

Hi Dave,
Please evaluate this proposed solution.
http://www.zodiacciphers.com/zodiac-new ... -john-rose
Thank you very much!!!
Wood

Looks like 58 of the 340 total letters are supplied. So only 17% of a solution has been found. I think many such partial solutions are possible. This solution will be more compelling if it covers more of the grid. Otherwise, you have to demonstrate that no other compelling partial solutions can be found. I suspect many can be. One good reason to suspect this is to consider the symbols covered by the 58 letters: There are 42 unique symbols. That means there are only a few repeated cipher symbols within those 58 positions, which means you get a whole lot of room to come up with all sorts of words.