Some operating systems do
provide a mechanism for generating random numbers from
input which is, in practice, impossible to
reproduce or guess. This is done by collecting data from
hardware events such as network device and disk interrupt
latencies and then generating numbers based on the
contents of this pool.
/dev/random and friends are useful for seeding
PRNGs, not necessarily useful for all your random number
needs (they tend to run out rather quickly: try generating
a key of some size with GPG, and spending half an hour
tapping the ctrl key to give it sufficient randomness). If
you want reasonably strong (unguessable) randomness, without
waiting for the OS entropy pool to fill up, you'll need to
consider which PRNG you're using.
And for that, I refer you to chapter 16 of Bruce
Schneier's
Applied
Cryptography.
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Found a typo in this node? /msg me
The hell with paco, vote for Erudil!
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