How does a cryptographically secure random number generator work?

Posted by Byron Whitlock on Stack Overflow See other posts from Stack Overflow or by Byron Whitlock
Published on 2010-03-15T18:44:32Z Indexed on 2010/03/15 18:49 UTC
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Filed under:

encryption

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cryptography

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random-number-generator

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random

I understand how standard random number generators work. But when working with crytpography, the random numbers really have to be random.

I know there are instruments that read cosmic white noise to help generate secure hashes, but your standard PC doesn't have this.

How does a cryptographically secure random number generator get its values with no repeatable patterns?

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