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A comment on There's Math.random(), and then there's Math.random(). Parent comment

Re:There's Math.random(), and then there's Math.random() by sverhagen on Friday February 07, 2025 @05:57AM (#42971300)
Those nanoseconds aren't really entropy then, are they?
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Re:There's Math.random(), and then there's Math.random() by lmm on Friday February 07, 2025 @06:35AM (#42971499)
They're entropy for most practical purposes. But there's only 1000 possibilities, so that's less than 10 bits' worth.
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Re:There's Math.random(), and then there's Math.random() by boothby on Friday February 07, 2025 @09:05AM (#42972636)
Especially if you're writing a file, the creation time is a big hint! Even nanoseconds won't help if you're leaking that many bits from your seed.
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Re:There's Math.random(), and then there's Math.random() by tomsmeding on Friday February 07, 2025 @10:01AM (#42973367)
That's milliseconds; nanoseconds are 1e-9 seconds. Still, the file creation time remark of sibling is pertinent.
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Re:There's Math.random(), and then there's Math.random() by lmm on Friday February 07, 2025 @08:04PM (#42979321)
I was thinking of the step from milli to nano, so yeah 1e6 not 1e3, 20 bits not 10. But the point stands.
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