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  Discussion about math, puzzles, games and fun.   Useful symbols: √ ∞ ≠ ≤ ≥ ≈ ⇒ ∈ Δ θ ∴ ∑ ∫ π -

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YZF
2012-04-25 02:17:43

I wrote a code generator a while back in Delphi.

The following code when deciphered would read ABCDEF

81012191411911941194119411941131815181419141181319013101813110

The only drawback with this is that if you wrote a whole sentence, it would be quite a long string, can anyone say how I have done this?
Jason

bobbym
2012-03-19 02:38:45

Hi Leornardo da vinci;

Welcome to the forum. Did you leave something out?

Leornardo da vinci
2012-03-19 00:15:09

you guys try to decipher this code by using the keyword ER this isnt a hard cryptic code here it is : JZFXAJUJSAZQZJZFXAJUJSAZQZPABOMIYBWMHVHTFHPWNJQWPLZAMEBBVLFAZHKAWTHQUAMEBWYAPVRMF

Code:

LordDannyl
2010-07-30 19:14:32

This all depends on the amount of "waffle". The way I would do it normally would be to take the first, 27th, 53rd etc and do a frequential analysis of those to determine the substitution for those, then repeat that for the 2nd, 28th, 54th and so on. However, the "waffle" would throw this analysis off; a little would probably still work because it would only affect the proportions marginally. However lots would seriously mess up the proportions (though it would still be breakable- just harder to get frequency analysis right. The most common would still correspond to "e", but then there's the trouble of working out what's waffle).


If you want a tough code, try this one:
|vrin||vditIJgbor{xtwiƻif{{}eqtmĮħ`Wooߦxdoptlt}`\|ôxqqyrrpy֨}}reĮĹĹ}|normIxynpn}}vg
big_smile

S.G. Shredmaster
2010-04-10 10:52:19

codes make my head hurt.........but theyre good for me.

bob farey
2010-03-10 03:57:01

I am not familiar with the terms, especially key. Hidden within the code is instructions on where to start, which direction to go, and details of the gaps between encrypted letters. Only the recipient knows which of the 900 letters in the code give these instructions. For example, a particular letter in the coded text would tell you which ROW to start in, so A=1, B=2  etc etc. Where to start in the row is more cunningly coded. The gaps between encoded letters are also defined in particular cells of the matrix.

I am not being difficult, folks, but you have to take any letter, ie 900 choices, then any other, ie 899 and so on.

So for a 20 word message that is 900 x 899 x 898..................x 880    =X

Then for EACH of these strings, you have to try all 26 letters of the alphabet.

So the total number of tries is X multiplied by 20 to the power 26

Within your tries you will find many many many words that string together.

I could have encoded the words in a different order to make it more difficult.......

I do not know how to calculate the total number of permutations, but 20 to the power 26 is pretty big......in itself.

bobbym
2010-03-08 13:21:09

Hi;

Then it is a problem with my browser, I will retry thanks.

calccrypto
2010-03-08 05:13:31

thanks for visiting. sorry my site isnt fully compatible with your computer

bobbym
2010-03-07 13:15:32

Hi calccrypto;

sorry for the repeat

No need, you did nothing wrong. Just stating the fact why no progress can be made with his algorithm.

Been to your site, wished that the tabs on the hash 2x pages were working for me.

calccrypto
2010-03-07 10:05:32

sorry for the repeat

bobbym
2010-03-07 09:47:36

Hi;

The point I made to him on another thread. Need to see the algorithm to prove it is difficult to crack. The output is no help at all.

calccrypto
2010-03-07 08:31:26

Kerckhoffs' principle

In cryptography, Kerckhoffs' principle (also called Kerckhoffs' assumption, axiom or law) was stated by Auguste Kerckhoffs in the 19th century: a cryptosystem should be secure even if everything about the system, except the key, is public knowledge.

Kerckhoffs' principle was reformulated (perhaps independently) by Claude Shannon as "The enemy knows the system." In that form, it is called Shannon's maxim. In contrast to "security through obscurity," it is widely embraced by cryptographers.

Show the algorithm but not the key. if it can be reconstructed without the key, it is breakable. i doubt that i can do it, but a really good cryptanalyst can probably do it

BOB FAREY
2010-03-01 00:16:24

So does anybody dispute that this method of encryption is uncrackable?

bob farey
2010-02-17 04:21:31

So you could not crack it, well here is the hidden message, c an you find where the message is in the text I have given you.

I could have given you 2000 letters instead of 900 without affecting the recipient's ability to transcribe it in 2 minutes.

Purely from the number of permutations to try, it is uncrackable, because the code letters are not consecutive in the grid I gave you...






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bob farey
2010-02-16 05:04:05

another clue, the message is in plain english, no l8trs, m8t

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