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| The Journal; A multi-level Challenge | |
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| Tweet Topic Started: Oct 13 2005, 03:07 AM (3,033 Views) | |
| Donald | Oct 14 2005, 08:49 PM Post #31 |
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NSA worthy
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Will do. And I acknowledge that in my ignorance I may have simply not designed this one correctly. Donald |
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| rot13 | Oct 14 2005, 08:54 PM Post #32 |
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Elite member
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Or it could just me be If nobody is able to get 9, 10 or 11 after a reasonable amount of time, you might give a hint telling us that a particular word or phrase occurs at a particular place. Or if you see a pattern that has letters that repeat on the same interval as the period, you could give that as a hint without specifying a location. |
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| Donald | Oct 14 2005, 08:59 PM Post #33 |
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NSA worthy
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I figured I would give it a few days, and if no one else gets it, I'll post a specific crib.
I SERIOUSLY doubt that. I'm willing to give it a few more days, just to see if anyone else makes progress, but considering our relative skill levels, the odds that I designed it poorly are FAR higher!
Which just goes to show, as I was saying to cows the other day, the problem ISN'T designing a cipher that is too hard to break by hand, the problem is designing a cipher that is hard, but NOT too hard. Donald |
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| insecure | Oct 15 2005, 12:01 AM Post #34 |
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NSA worthy
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Just a quick update (or rather, lack thereof)... I've cracked 1 through 5, but I haven't even started on 6 yet. Alas, some of us have - well, I won't say "better", but other things to do as well as cryptanalysis! So I hope you don't launch into a detailed discussion of 6+ just yet. |
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| insecure | Oct 15 2005, 08:56 AM Post #35 |
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NSA worthy
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Page 6 cracked. |
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| Donald | Oct 16 2005, 04:57 AM Post #36 |
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NSA worthy
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Congratulations! And now, an apology. After discussing Page 9 with rot13 via PM, I've had to concede that I simply did not leave enough of a hole for people to be able to get in. I'm not saying it's unbreakable, just that it's too hard to be FUN to break with pen and paper. rot13 has given me advice on how to fix it, for which I am VERY grateful. As soon as I get an answer back from him on one question, I will post a hint for page 9 that should make it more approachable. rot13 spent a LOT of time working on this cipher assuming it had been designed well. I do appreciate his effort and apologize for the difficulties. Donald |
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| Donald | Oct 16 2005, 08:06 PM Post #37 |
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NSA worthy
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Life is getting in the way, sorry for the slowdown.
I am working on changes to page 9, 10 and 11 to make them more approachable. Hopefully I'll have some corrections up late tonight. Which will hopefully be before anyone else GET'S to page 9 anyway. Donald |
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| Donald | Oct 17 2005, 06:14 AM Post #38 |
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NSA worthy
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Ok folks, I believe the problems are all fixed. Again, thanks to rot13 for his help! I modified the ORIGINAL POST to the new corrected versions of the ciphers. Please refer back to it for fresh copies of page 9 through 12. The main problem seemed to be that I didn't know how to properly use cribs. I wasn't identifying them by unique patterns so much as trying to locate them by identifying several key letters (or digrams). Which is simply too hard for a pen and paper challenge. Possible, but VERY hard. (I'll post some notes on what I've learned about cribs) Page 9 COULD be decrypted as is, but it was VERY difficult to do so. The path I was envisioning to break into it worked, but several of the steps involved were unlikely to occur to someone who was not intimately familiar with the cipher and plain text. SO, I have added a few hints to page 9 that will help step you through the process I was envisioning, just in case your brain isn't twisted the same way mine is. AND, at rot13's advice an explicit crib was chosen from the text, as is. Note that even if you figure out my original way into the cipher, it's still a long climb to complete decryption, so don't be ashamed to use this extra crib.Page 10, the playfair, could also be decrypted as it was using shotgun hill climbing or simulated annealing. There is a program available online that cracks that particular message in about 2 seconds using simulated annealing. But where is the fun in that? (unless you wrote the program!) Now doing shotgun hillclimbing or simulated annealing by hand is certainly possible, but it's a long painful process. If you are going that route, I recommend you write a program to do it. Which WOULD be fun! :), BUT, It's MUCH easier to work it from a crib. However, due to my unbelievable ignorance, the cribs I had provided were ALL pretty much useless for playfairs. They didn't have any patterns that would help you locate them. <sigh> SO, I modified the text of page 10 slightly to include a very good (and quite reasonable in context) playfair crib. I recommend you use the crib. It is really MUCH more practical for this kind of challenge. AND, you can figure out what the crib is entirely on your own without actually highlighting the hint text. Page 11 had an error. Well, it wasn't really an ERROR. It was just that I hadn't used the exact encryption scheme I THOUGHT I had. The alphabets were shifted in a way that made the cipher much harder to break, and it was already too hard the way I had meant it to be!!! So, I re-encrypted Page 11 using the properly shifted alphabets, AND I took the oportunity to very slightly modify the text and turn a lousy crib into an excellent crib! Again, the crib was designed to be something you could find without even needing to read the hint text. Just look through everything you have already decrypted for important phrases or names that would make a good crib at this ciphers period. That's how *I* found the crib, so you can probably find it. If not, some hints have been provided to help you identify it. With the new crib(s) this cipher may still be a challenge, but I don't think you will find it impossible. Page 12 did NOT have anything wrong with it, but had to be modified to stay consistant with the changes in page 10 and 11. Yes, that *IS* a hint, but nothing you wouldn't have figured out by the time you got to page 12 anyway. So, one more time, I can't say thank you enough to rot13 for his patience and help in getting page 9 fixed and teaching me about the proper use of cribs so that I could fix page 10 and 11 as well. You should find the rest of the challange a reasonable and (I hope) fun experiance now. Donald |
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| rot13 | Oct 17 2005, 09:59 PM Post #39 |
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Elite member
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The crib on 10 is very helpful. It gave me enough information just in working out where things go that I was able to guess the keyword and shape of the alphabet. |
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| rot13 | Oct 18 2005, 10:00 PM Post #40 |
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Elite member
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Excellent crib on number 11. |
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| rot13 | Oct 18 2005, 11:23 PM Post #41 |
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Elite member
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Okay, on number 12, I have tried everything that seemed logical. I better put this in white just to make sure I don't give anything away to someone who doesn't want to know. Is it only letters? It seems like only 10 and 11 are involved, but even following the "direction" I can't make it come out to anything legible. I thought it might be a one-off problem, but that's not helping either. Any suggestions? |
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| Donald | Oct 19 2005, 02:15 AM Post #42 |
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NSA worthy
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I think you are thinking too small. [hint] Think Beale but numbered according to the "direction" in the hint. Also Notebook is one word. Words containing apostrophe's are one word. [/hint] If this is something you've already tried, we will need to compare some detailed notes in a PM to see whats wrong. Donald |
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| rot13 | Oct 19 2005, 12:59 PM Post #43 |
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Elite member
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Done! TCGZYIKNPEGACYNGRVZRBVXPFZPWWCNAAUGQKMEUOELLR |
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| rot13 | Oct 19 2005, 04:32 PM Post #44 |
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Elite member
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Donald, this was a great challenge! The cribs you picked for the last couple were just right. They gave you enough information to go on but didn't crack the thing wide open, and they were reasonably easy to place (the playfair did take me a little while, tho). Doing the thing as a story was fun, I was anxious to see what would happen next. |
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| Donald | Oct 19 2005, 06:31 PM Post #45 |
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NSA worthy
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You're exceptionally kind. I'm just sorry you had to work through so much guff as I learned how to set up a proper challenge. Thank you for all your help. AND, congratulations! This was even harder than I meant it to be and you still climed all the way to the top! For the other folks slogging their way through this. As soon as I wrap up some questions on page 12, I'm going to modify the original post again to include a hint for every single cipher. That way no one should have to get stuck just because they didn't know what the encryption algorithm was. I think that should leave this challenge as very difficult, but still possible. Donald |
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