Sorry to detract from the DNA issue but can we please just celebrate the excellent work that has been done by the Cipher gurus on this board. They deserve the praise. Well done guys you have succeeded where some many of us have failed.

Impressive feat, but not seeing much there — other than confirmation that he may have had a legitimate background in coding/encryption.

Congrats, glad those of us ready to see justice see a step in the right direction.

So…Zodiac was playing dumb with the construction of his original cipher?

I don’t think he was playing dumb, I don’t believe he had much experience with ciphers. The 340 he put a bit more effort into it, I don’t think he had to be a genius to put the 340 together. He just needed to be more clever is all. For a long time, I felt it was done in a mirror image.

The fact that the first one was solved almost instantly, the second one took 50 years and technology that didn’t exist at the time, suggests to me he didn’t know much about ciphers at all.

Basically, he was using techniques out of a book, tried something, was disappointed at how easy it was, and then massively overcompensated because he didn’t have enough knowledge to correctly gauge difficulty. From "way underdone" to "waaaaaaaay overdone." If he’d had more knowledge, rather than just picking stuff out of a book, he would have known the 340 was basically not solvable at the time and would have "toned it down" a bit.

Or so it appears to me.

The fact that the first one was solved almost instantly, the second one took 50 years and technology that didn’t exist at the time, suggests to me he didn’t know much about ciphers at all.

Basically, he was using techniques out of a book, tried something, was disappointed at how easy it was, and then massively overcompensated because he didn’t have enough knowledge to correctly gauge difficulty. From "way underdone" to "waaaaaaaay overdone." If he’d had more knowledge, rather than just picking stuff out of a book, he would have known the 340 was basically not solvable at the time and would have "toned it down" a bit.

Or so it appears to me.

Agree 100%. He meant to make it harder, but not decades-later kind of harder. It was more a lack of knowledge than some genius-level understanding that made it so hard to solve.

It’s actually really easy to make up a cipher and intentionally OR unintentionally make it very hard or impossible to solve. Homophonic ciphers on their own can be difficult as it is, and combined with some crazy transposition (and Zodiac’s had errors….) you can make a real mess.

This is also why I believe that the people who are trying to find "another solution" or a "message-inside-a-message" etc., are totally on the wrong track. Plus, the mathematics of it and Shannon’s law of entropy all but assure that the solution that has been found is the one and only correct solution.

Even if you COULD put multiple messages in a cipher like the 340 (and it’s mathematically impossible, really) I don’t think Zodiac had the knowledge to even attempt that. (Plus, it’s just not possible anyways!)

AMEN

I believe the following has been mentioned before, let me just say though I thought it was a good point

Why did Zodiac commit to a cypher(340) information that he also wrote out in plain English? Which came first?

As for me, i . It will take a DNA match to begin a renewed investigation but corroborating evidence will also be required. A DNA match is just the first step to closing the case.

Indeed. The thing is do LE have a definite DNA match for Zodiac? I know this topic has ben discussed ad nauseam, but am I correct in believing that partial DNA has been found under one of the postage stamps adhered to a Zodiac envelope? It’s someone’s DNA. Considering the recent success of solving high profile cases of serial murder by the use of DNA, I can’t see why LE can not get their backside’s into gear with regard to the Zodiac case. Has the case become low profile? Are LE working on the assumption that Z is deceased?

Even if you COULD put multiple messages in a cipher like the 340 (and it’s mathematically impossible, really) I don’t think Zodiac had the knowledge to even attempt that. (Plus, it’s just not possible anyways!)

One way to do it would be to create an innocuous-seeming plaintext but hide a message using steganographic methods.
A contemporary example: https://techcrunch.com/2009/10/28/schwa … en-finger/

And it IS possible to encode two different plaintexts using homophonic substitution:

http://www.zodiackillersite.com/viewtop … =81&t=4820

But Z340’s alphabet is not big enough to support it, methinks. I was able to make a 2-plaintext message, as a "toy" example, using a 64 symbol cipher alphabet and a very limited plaintext alphabet. It’s posted in that link.

Dave, yep, that’s right. But I really meant "another totally different message" in the 340 specifically. With the plaintext being 340 characters also, and only 64 symbols in use, there aren’t enough symbols to do that.

Of course he could have included a "sparse" message using the symbol assignments, and I think he probably did, with the ZODAIK at the end.