« Winners for Challenge 4 | Main | Scoring for Challenge 6 »
November 01, 2005
November
The new month is upon us so the front page has been spring cleaned. Old messages can be seen by clicking on the links to the right (including the calendar) All the best,
Posted by Harry at November 1, 2005 03:11 PM
Comments
If you wish to leave a comment please act responsibly. No personal or innapropriate comments should be made. Concerns about a comment should be emailed directly to us here. Hints about the challenges may be blocked or held back at our discretion. We reserve the right to refuse to publish comments without entering into a discussion about why, and to censor comments as we see fit. Please be patient if it takes a while for your comments to be approved.
this one: http://news.bbc.co.uk/1/hi/england/hampshire/4390048.stm
Posted by: cecil at November 10, 2005 07:04 AM
What fire?
Posted by: at November 9, 2005 10:35 PM
why is 5b the same as 4b?
Posted by: ellz at November 9, 2005 08:54 PM
I ask every week, sorry.
But...
Please could you tell us what the timing intervals for challenge 6 will be. I need to know how much of a hurry I need to be in when trying to get home on Thursday.
Thanks
[See the log. Harry]
Posted by: tom at November 8, 2005 09:23 PM
Did you manage to avoid getting burned in the fire a week ago Harry? Is it going to affect the challenge?
[It was close! There shouldn't be any affect, but people are very busy here as you can imagine. Thanks for the concern. Harry]
Posted by: Anne O'Rack at November 8, 2005 06:04 PM
was there any difference between 4b and 5b?
Posted by: sara at November 8, 2005 07:31 AM
Why does the main page frequently end up devoid of any news? When I looked at it today the part where the news appears was empty and I had to click on the links on the side to post this.
[I'm not sure, I think it only posts the last week's news, and we are a little short of news at the moment. Harry]
Posted by: Ruth at November 7, 2005 05:39 PM
Anyone need any help with Challenge 5? I'm feeling generous :)
Posted by: cecil at November 7, 2005 07:03 AM
YAY done the cipher... and staying up to date... all because of my cool partner... :D thanx Shev Shev! But i dont even know what the story line is! woops...
Cynthia
Posted by: the3blobs at November 4, 2005 09:17 PM
Okay, maybe it wasn't such a good example!
But the rest of what I said still stands, and if you're looking for a hint, I put it there for a reason!
Posted by: harry de voil at November 4, 2005 03:39 PM
Actually, that is incorrect. The ADFGVX cipher is not just a transposition, although it is a good example of one in use. It consists of two stages, the first substituting each plaintext letter or number to a digraph using only ADFGVX letters, and the second a transposition cipher (in the Cipher Challenge, the conventional method was not followed exactly, but it was very similar). By combining substitution and transposition you get a simple way of making a much stronger cipher.
Posted by: Jason B at November 3, 2005 11:06 PM
Actually, the ADFGVX was BOTH a transposition AND a substitution. And the substitution replaced each letter by a pair. But the transposition operated on individual ciphertext letters, which meant they were really half-letters. That was why it was so tough.
Posted by: John at November 3, 2005 08:18 PM
Can anyone out there help me? I've been pouring over Challenge 5 part B and I still can solve it. I have got to about half way and see no apparent way of solving it. Can anyone give me a hint so I can crack it?
Posted by: Nat at November 3, 2005 07:51 PM
If u use a program it might not work as there are NUMBERS in it! Do it by hand or excel
Posted by: Nebster at November 3, 2005 07:48 PM
Look for anagrams of common words that have been in previous messages if you are stuck
Julian Bhardwaj
Posted by: Julian Bhardwaj at November 3, 2005 06:51 PM
The ADFGVX cipher is NOT a good example of a transposition cipher. It is a fractionating subsitution cipher, and as such has both a substituion and a transposition element.
Posted by: OcelotIIX at November 3, 2005 06:49 PM
Actually, an ADFGVX cipher is a substitution followed by a transposition.
Posted by: Ben at November 3, 2005 05:17 PM
hey harry whats going on there is still no challenge 6!!!
[Doh! Check the schedule on the standing orders. It comes out on November 10th, Harry]
Posted by: Martyn Compton at November 3, 2005 04:53 PM
There are two types of cipher: transposition and substitution.
Substitution involves changing the actual alphabet so that a letter in the ciphertext is (usually) different to its letter in the plaintext. An example of this is the Caesar shift cipher.
In a transposition cipher the letter values are not changed, but instead are moved around according to a key. An easy example of this is the ADFGVX cipher.
If when running frequency analysis the letter values are the same as you would expect in an english text, a transposition cipher has probably been used.
Posted by: harry de voil at November 3, 2005 01:28 PM
If you have solved 4B then you'll have a better chance of solving 5B
Posted by: Clever Code Cracker at November 3, 2005 07:53 AM
tom,
Do you know what kind of cipher it is? Have you done a frequency analysis? Do you know where the message came from? Have you already got messages from the same source? Did they have anything in common? (I'll give you a clue - the answer is YES!)
Hope that helps.
Posted by: cecil at November 3, 2005 06:34 AM
Perform a frequency analysis first. What do you notice about the most common letters?
This should point in the direction of what kind of cipher this is.
Posted by: cipherbloke at November 3, 2005 06:25 AM
how do you solve 5b plz help
[Anyone got any not too easy hints? Harry]
Posted by: tom at November 2, 2005 06:57 PM
Iz - I suggest you look at the comments on the previous challenge, most people had the same problem with that challenge too.
Posted by: Robert at November 1, 2005 10:43 PM
iv workd out da beginn of 5B but den midway its strtin 2 make no sens wotsoeva!!!wots hapend? gimme a clu plz...
Posted by: iz at November 1, 2005 08:26 PM