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Topic Started: Aug 26 2005, 08:28 PM (1,139 Views)
insecure Oct 21 2005, 10:30 PM Post #46
Elite member
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 No, there's no mathematical link (or at least, if there is, it's more likely to be a shift cipher, which is a trivial special case of a "mono").

Having placed 'e', 't', and perhaps 'a', you are probably in a good position to place 'h' (because of 'the'). You may well be able to place 'n' too (words ending in 'ant' and 'ent' are quite common). You proceed linguistically, rather than mathematically.

If word spacing has been preserved, you can do pattern analysis on some words. For example, the word "clinician" has the pattern 123431354. See if you can work out why. Here's a simpler example: "amass" has the pattern 12133.

But the most important way to crack a monoalphabetic substitution cipher is to switch on your brain and start thinking about what it is and why frequency analysis can crack it. Once you understand that, you'll see why nobody with any sense uses monoalphabetics for encryption.
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cows Oct 22 2005, 06:32 AM Post #47
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 Thanks for the help -

So have all of you already cracked part a and b?
Everything is possible,
The impossible just takes longer
If we do not know what a particle is doing then it is allowed t do everything possible simultaneously.
"Anyone who can contemplate Quantum Mechanics without getting dizzy, didn't understand it."
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insecure Oct 22 2005, 08:02 AM Post #48
Elite member
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 I didn't bother with B, since I assumed it was A you needed help with.

I did, however, take a look at it, and I think you're right that 0 and 1 stand for dot and dash or possibly dash and dot. The first step, then, is to find out which of those interpretations leads to legal Morse code letters. The second step is to replace the entire ciphertext with English letters. Then I suspect it will turn out to be just another monoalphabetic substitution cipher, which of course you will be able to solve in the normal trivial way.
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Revelation Oct 22 2005, 09:30 AM Post #49
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Administrator
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 He is right, A is not that hard. You will absolutely find the 'e'. The 't' will then pop out as the highest frequency.

What is harder, is my polyalphabetic substitution cipher. :)
RRRREJMEEEEEPVKLWENFNVJKEEEEEAOLKAFKLXCFZAASDJXZTTTTTTTLSIOWJXMOKLAFJNNKFNXN
RAGRBAQEMHIGDJVDSEOXVIYCELFHWLELJFIENXLRATALSJFSLCYTKLASJDKMHGOVOKAJDNMNUITN
RRRRLJVEEEEECLYVYHNVPFTAEEEEEMWLMEIRNGLARWJAKJDFLWNTIERJMIPQWOTZEOCXKNUBNXCN
RJIRPOWEANFUSNCZVDVZNMSFEKLOEPZLDKDJWSAAAAAAAOERHJCTNCKFRIMVKSOFOMKMANREWNBN
RZUDRGXEEEEENFQIDVLQNCKNEEEEEDGLLLLLLAWIOSNCDARLODMTOEJXMILDFJROTKJSDNLVCZNN
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cows Oct 22 2005, 05:14 PM Post #50
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 Ya I had a look at that - *shudder*

Maybe i am not that good... yet... :)

I like the look of it though, it's kinda like the cipher challenges - forum of that is here.

Oh and guys - i don't know if you've ever heard of it, www.stumbleupon.com

It is where I found this forum, it picks random websites and displays them, kind of cool that it linked me here though.

p.s. i am not saying this website is good in any way or that it has anything to do with ciphers but just wondered if you knew that the forum was on it's database??
Everything is possible,
The impossible just takes longer
If we do not know what a particle is doing then it is allowed t do everything possible simultaneously.
"Anyone who can contemplate Quantum Mechanics without getting dizzy, didn't understand it."
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