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December 08, 2005
Challenge 8 and timing
Well, here it is, the last part of the Challenge. Part A should be straightforward, but part B is horrrible! I have written a report on the cipher machine and those of you who can programme can use the report to start coding up a simulator and trying it out. If I get any other info about the machine (and I will) I will post it here.
If you have no hope of writing a programme you could still have a go at deciphering the message by hand, by building a "Pringle tube" Enigma machine. I'll explain how later, but you will need to know more or less all the settings to do this as it would too long to change the wiring diagrams. Anyway it might be a fun Christmas project.
The scoring for Challenge 8 will be the same as the scoring for Challenge 7.
There is a pdf document with a report on the cipher machine that you will need to download. If you are having trouble email me and I will email you a copy, but please do try first.
Good luck to all of you.
(I'll announce the part 7 winners tomorrow)
Posted by Harry at December 8, 2005 04:35 PM
Comments
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Pleez can we have a new thread? Ta.
Posted by: lbow at December 9, 2005 09:07 AM
Blah, still can't get the possibilities down sufficiently without some major "probable" guesses... don't suppose Richard wants to give us a clue? Ah well, till 3:30 then :P
Posted by: Ian at December 9, 2005 08:56 AM
Haha! Just had a HUGE flash of inspiration! Hoho!
Posted by: Richard at December 9, 2005 08:15 AM
Abi and others,
I don't want to give away too much but both the wiring diagrams can be greatly improved if you change the hue and saturation and other things. Play around a bit and see what you can get.
Posted by: cecil at December 9, 2005 07:29 AM
Anybody else awake still, comrades. I'm completely stuck. What is the point of running a program with this number of permutations? I feel really stupid.
[You are not supposed to be able to do it today! Just get some sleep. We'll give you some more data tomorrow after 3.30pm. Harry]
Posted by: Ben Caller at December 8, 2005 11:57 PM
Ahhhhh...I see now! I was being very very silly before - thanks!
Now to the REAL work ;)
Kati
Posted by: Katriel Cohn-Gordon at December 8, 2005 10:38 PM
Can you give us any idea when then the next bit of information will come out? We will be at school tomorrow, so will find it hard to be always checking to see whether there are new hints.
Posted by: Naomi at December 8, 2005 10:35 PM
No offence to your artistic skills Harry, but are the wiring diagrams intentionally incomprehensible (some of reflector, and most of the rotor wires are indistinguishable from one another), or are we meant to be able to get these wirings from them?
[Its intentional. It is supposed to simulate the effect of trying to trace all the wirings under pressure in a raid on the Weather Station. The colours are not really indsitinguishable, although some are similar. You can distinguish the yellow from the green and so on. I can clearly trace all the reflector wirings without difficulty. You might want to adjust your colour settings on your monitor Try looking at the image of a real Fialka rotor here to see how hard it would be without the colour coding! Harry]
Posted by: Abi at December 8, 2005 10:29 PM
For example, the first 5 letters of the published Morse are ".----". How am I supposed to know whether this is . (=e), .- (=a), .-- (=w) or even .--- (=j)? Tree search!
Kati
[Like I say, there are slashes between the Morse characters as usual :) Harry]
Posted by: Katriel Cohn-Gordon at December 8, 2005 10:22 PM
Erm...not sure I follow you Harry.
I can't translate the published Morse into characters because it is not spaced, so I can't tell the characters apart... No Morse character is more than 4 letters so they can't be individual chars?
Kati
Posted by: Katriel Cohn-Gordon at December 8, 2005 10:16 PM
How many people have cracked 8B so far? (And thanks for making the timing interval not an hour!)
[None. Good isn't it. Harry]
Posted by: Ian at December 8, 2005 10:14 PM
To Robert, I suppose it must be the fast/slow option. I initially thought they would turn evenly, but that would mean that after 18 rotations the rotors would be back to the beginning, so there would basically be an 18 alphabet vigenere, making the machine pointless.
Posted by: Ian at December 8, 2005 10:07 PM
Presumably they don't turn in sync cos then it would just be like 1 turning 2 places at a time (or have I missed something?)
Posted by: Ruth at December 8, 2005 09:49 PM
Just a request for clarification - in the pdf it states that the rotors "turn in opposite directions". It also states the machine resembles an enigma. Does this mean that the rotors have similar stepping characteristics to an enigma (i.e. the first rotor is fast, and clicks the 2nd rotor onwards once per revolution), or that both are in continuous rotation?
Posted by: Robert at December 8, 2005 09:42 PM
Hiya! Can someone tell me how you can crack 7B?
Posted by: Sam at December 8, 2005 09:30 PM
Don't worry Ocelot - I failed too :$ :P.
Am I missing something obvious in the Morse code or do I need to do a tree search just to find the letter spacings, let alone the letters?
Kati
[Have you tried converting the published Morse to characters? What did you get? Harry]
Posted by: Katriel Cohn-Gordon at December 8, 2005 08:55 PM
Since I have the solutions to previous challenges all nicely typed up with punctuation checked with the master copy for my reference, Harry do you want me to post them for the last few challenges so people who haven't done them can see them?
[That would be great! Thanks, Harry]
Posted by: cecil at December 8, 2005 08:36 PM
Well, I've made a fiendishly good program which removes all wires except the colour of your choice, that's helped me to get the possibilities down again.
Don't suppose you're allowed to tell us how many colours you've used?
[That's right! Harry]
Posted by: Ian at December 8, 2005 08:36 PM
Harry, yor reports refers to contacts on the front and the back - how do these correspond to the pictures, ie does the front correspond to the outside contacs and the back to the inside contacts?
[I'll have to check my notes! I guess I will say something about this some time. Harry]
Posted by: Stephen Harris at December 8, 2005 08:30 PM
Grr, these diagrams are annoying! But also hurrah! I thought I still had 1981355655168 possibilities left for the wiring combinations of the first rotor, but I realised that I've really only got 214990848, which is great, but I don't really know how I'm going to get it computed... and that's times 9 for the reflector, and hopefully the second rotor will be cribbed into action. Should start programming soon! And still no points lost! (For another 2 minutes)
Posted by: Ian at December 8, 2005 08:00 PM
WOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO! i did 8a!!!!!!!!!!!!!!!!! But Harry, why? why? why? ***********************
i wasn't kidding about b, though, i really don't understand what all the comments are about!!!!! can you please explain the rotor machine thing kind of more clearly. sorry, i'm very dense+ slow on the uptake.
[Think of it as a training exercise! Harry]
Posted by: lara at December 8, 2005 07:31 PM
Am i incredibly dense? i can't make head or tail of what everyone else is talking about. i'm so lost. please help.
Posted by: lara at December 8, 2005 07:15 PM
Harry
I would like to copy and paste the correct solutins to cipher 6 and 7 so that I can check to see how much I got right, as I did not submit them as I didn't finish them. How do I do it? If you try they just change back into the morse code.
Thanks
[At the mmoment you can't they are just images. I'll try to get a moment to put the solutions up as text. Harry]
Posted by: richard at December 8, 2005 07:13 PM
Harry, is this challenge physically possible for a year 9 who knows no programming whatsoever to crack?
[Not at the moment. You could have a go later when most of the settings are known. Harry]
Posted by: lara at December 8, 2005 07:03 PM
Also wandering whether the 15 and -35 on the crib could possibly indicate the position of the rotors. ((I can't program but am determined to try my best. Even if it is simply determining as many connections as I can.) Don't give up everyone. It MUST be possible.
Posted by: x at December 8, 2005 06:54 PM
and the 36 as the wind speed of the crib is also coincidental?
[Yes, spooky isn't it! Harry]
Posted by: x at December 8, 2005 06:48 PM
1296 seems to be a highly significant number.
(36 squared) Please don't say that we have to do what we did in challenge 6B. Also 36 is the number of connections so is that significant at all?
[All entirely coincidental (although it wasn't going to be before I relented). Harry]
Posted by: x at December 8, 2005 06:44 PM
When are you going to the next bit of information Harry? What will it be? Are we going to get the cipher for the Weather Station crib plaintext?
[I'll publish something tomorrow. Over the next few days we will see how people get on before deciding what to publish and when. Harry]
Posted by: lbow at December 8, 2005 06:40 PM
What about chal 6 winners? Or did I miss that post?
[I'm not sure. Maybe I missed it! We did write to the winners of round 6, but I might not have published the list. I'll check and if I didn't I'll announce it with the Challenge 7A winners tomorrow. Harry]
Posted by: Ruth at December 8, 2005 06:27 PM
Harry, can't you just of and take another photo of the second rotor?
[Are you kidding? I risked my life going on board the first time. Harry]
Posted by: Photo at December 8, 2005 06:18 PM
Sorry about that earlier comment
Must be a cryptographical version of a Rorschach test, and it looks like I failed :P.
Posted by: OcelotIIX at December 8, 2005 06:03 PM
HOORAY I finally got the right number of characters. You were right Harry, I forgot the line breaks...
I'm pretty sure that I don't stand a chance at 8B, due to complete lack of programming skills, but it was nice to know that I at least got the ciphertext :). It's also great to know that I got this far (42nd overall at last check) the first time I tried the challenge.
[Well done! Hope you try next year too. Harry]
Posted by: David W at December 8, 2005 05:57 PM
Can we assume that these wires don't have severe bends in them?
[I hesitate to answer that, but it's a reasonable working hypothesis. There is nothing to stop a pin being connected to the same position or a neighbouring position so that would need a bend. Harry]
Posted by: Ian at December 8, 2005 05:55 PM
How long would you estimate it will take the average challenge taker to crack this? Have you had any correct submissions for part B or A?
[Part A shouldn't take too long. We have had some corect solutions to that. I don't think anyone could do part B yet, and I'm not sure how long it will take. Harry]
Posted by: lbow at December 8, 2005 05:53 PM
ooh! done it now... but i had tried everything on it! even enigma programs... and nothing was working!
[I was trying to be kind. Harry]
Posted by: charlie at December 8, 2005 05:51 PM
Are there any timing intervals?
[Same as last time. Harry]
Posted by: Ben Caller at December 8, 2005 05:47 PM
I'm colourblind. Copy the picture into Paint, and turn each colour of wire into RGB. I've got the reflector down to 9 possibilities.
[Great hint! Harry]
Posted by: Ian at December 8, 2005 05:44 PM
how long does it take to clean up a photo? can you give us another clue then?
[Ages! This is only 1959 so we don't have digital tools yet. No clues for a while. Harry]
Posted by: jgkjgky at December 8, 2005 05:36 PM
all you people are doing b! can someone PLEASE give me a hint on A!!!!!
[What have you tried? Harry]
Posted by: charlie at December 8, 2005 05:27 PM
Does the 1296 character count include numbers and symbols? Also, I seem to have a lot of non-English symbols...
[That will be because you left line breaks in before decoding the Morse. Harry]
Posted by: David W at December 8, 2005 05:18 PM
Harry, have you considered those of us who are colour blind? I have got stuck with the plugboard which is a very big job. Good thing I'm in a big team!
[I did worry about that. There are also probably other visually impaired competitors, but I could not figure out a way of doing this other than just writing down connections, and that is too easy and too dull. If you need additional help with this I hope friends or family will get involved in untangling the pictures. Harry]
Posted by: lbow at December 8, 2005 05:18 PM
Harry, can you get your specialists to clean up the photo of the second rotar, please. Thank you.
[They are working on it as fast as they can. I'm sure it will be done by January. At the latest. Harry]
Posted by: NEED HELP at December 8, 2005 05:17 PM
does part B have 1294 characters?
[I still think it is 1296, but I'll check later. Harry]
Posted by: Luke at December 8, 2005 05:13 PM
Harry,
CHANGE YOUR LAST COMMENT.
You aren't supposed to tell our parents we only need one pringle can!
Get rid of the comment before our parents see, so we have a valid excuse for eating loads.
[Whoops sorry that was a typo. You need one hundred. (Does that work?) Harry]
Posted by: Annoyed at December 8, 2005 05:09 PM
Is 1,594 the number of characters I should have for part B, or am I way off?
{I make it 1296. Don't forget to remove line breaks. Harry]
Posted by: David W at December 8, 2005 05:08 PM
Harry -The pictures of the rotors look like they've been drawn on paint. Couldn't you have least used different colours for all the different ones?
[Errr no. That's deliberate! Harry]
Posted by: Prucilla at December 8, 2005 05:05 PM
Harry, next time, check for typos. At least, I hope it's a typo, (Referring to 8a) as it's otherwise slightly disturbing.
[Errr actually it's "These men" and its not a typo. Harry]
Posted by: OcelotIIX at December 8, 2005 05:05 PM
ok... dont want to sound stupid but you three have already done it... and im not even close... can any of you tell me if its a cipher we've already come across this year?
Posted by: charlie at December 8, 2005 05:02 PM
What are the timings for this round?
Sorry I should have said. Same as last time! Harry]
Posted by: Matt at December 8, 2005 05:02 PM
How many people do the challenge at school. We do.
Posted by: cynthia at December 8, 2005 05:01 PM
y doesn't the pdf link work?
[I don't know, it works for us. Harry]
Posted by: Luke at December 8, 2005 05:01 PM
Can't you give us a clue?
[We have four weeks to crack this. I think a clue today would be premature. Have you read the report on the machine? Harry]
Posted by: Georinay at December 8, 2005 04:59 PM
Done part A.
I cannot programme however. Bye beye all chance of doing part B.
Better start eating those pringles
[I don't want to be accused of encouraging a junk food addiction so I should point out you will only need one Pringles can. harry]
Posted by: JasonWhite at December 8, 2005 04:48 PM
WOOOOOOOO!!! CHALLENGE 8!!!
Too early for a hint? :P
Nice to see the pdf attached, makes life a bit easier!
Posted by: Ian at December 8, 2005 04:43 PM
I have converted the original dots and dashes using more code,giving me a set of numbers. Do i have to convert them into morse then into text using the same method as before?
[Why not try it and see? Harry]
Posted by: Luke at December 8, 2005 04:41 PM