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Cryptography In C
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Cryptography is based on algorithms (and some very heavy mathematical analysis), not choices of implementation language.
http://en.wikipedia.org/wiki/Cryptography
> I mean that can be acctualised using a C program.
Since C is a Turing complete language, if you have an algorithm, then you can express that algorithm in C.
> I think Substitution chiper is good
I look forward to emptying your bank account of all your money - as would any other person with even basic knowledge.
http://en.wikipedia.org/wiki/Cryptography
> I mean that can be acctualised using a C program.
Since C is a Turing complete language, if you have an algorithm, then you can express that algorithm in C.
> I think Substitution chiper is good
I look forward to emptying your bank account of all your money - as would any other person with even basic knowledge.
But since there is a definate pattern here (something is getting replaced or subsituted by something) it always is easy to crack to Substitution or Caesar Cipher. So it won't matter much no matter how long strings you use since there will always be a simple formula which the hacker will look for.
Chossing some tougher 64 bit or 128 bit algos which are commonly used nowadays would be a much better choice. Some of them are RSA (Rivest Shamir Adelman) , MD5 Hash algorithms etc.
Chossing some tougher 64 bit or 128 bit algos which are commonly used nowadays would be a much better choice. Some of them are RSA (Rivest Shamir Adelman) , MD5 Hash algorithms etc.
Last edited by ~s.o.s~; Jan 8th, 2007 at 12:37 pm.
I don't accept change; I don't deserve to live.
> choose the replacement for first character from first string,
> for second from second string,
So you're saying that if you have 4 strings as your key
that taking 't' 's' 'r' 'd' .... and the other 12 letters in some order, that the result is a lot more secure than using "thisismywordgrid" as the key?
Yeah, maybe it will fool a dictionary based attack, but it certainly doesn't fix any of the frequency analysis attacks (a problem faced by a lot of substitution cyphers). A good algorithm has to stand up to all known attack forms, not just those that can be done with pen and paper.
As for a chosen plaintext attack, that's just going to reveal the key straight off.
http://www.interhack.net/people/cmcu...e-oil-faq.html
Like has already been said, you need to spend a good long time doing lots of research on your own. Cryptography is a large and very technical subject. A brief Q&A on a message board isn't going to cut it.
> for second from second string,
So you're saying that if you have 4 strings as your key
"this" "ismy" "word" "grid"
Yeah, maybe it will fool a dictionary based attack, but it certainly doesn't fix any of the frequency analysis attacks (a problem faced by a lot of substitution cyphers). A good algorithm has to stand up to all known attack forms, not just those that can be done with pen and paper.
As for a chosen plaintext attack, that's just going to reveal the key straight off.
http://www.interhack.net/people/cmcu...e-oil-faq.html
Like has already been said, you need to spend a good long time doing lots of research on your own. Cryptography is a large and very technical subject. A brief Q&A on a message board isn't going to cut it.
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