Why are primes important in cryptography?

Posted by Michael Stum on Stack Overflow See other posts from Stack Overflow or by Michael Stum
Published on 2009-01-13T17:12:17Z Indexed on 2012/11/14 17:01 UTC
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One thing that always strikes me as a non-cryptographer: Why is it so important to use Prime numbers? What makes them so special in cryptography?

Does anyone have a simple short explanation? (I am aware that there are many primers and that Applied Cryptography is the Bible, but as said: I am not looking to implement my own cryptographic algorithm, and the stuff that I found just made my brain explode - no 10 pages of math formulas please :))

Thanks for all the answers. I've accepted the one that made the actual concept most clear to me.

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