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A comment on A hacker stole $31M of Ether – how it happened, and what it means for Ethereum. Parent comment

Re:A hacker stole $31M of Ether – how it happened, and what ... by jessriedel on Friday July 21, 2017 @12:13AM (#14818014)
Formally, the condition isn't "never use a one-time pad with the same key numbers" it's "make sure the key numbers of each pad are statistically independent of each other".

Not that it matters. The sqrt(n) birthday effect isn't sufficient to overcome the exponentially low chance of a one-time pad collision for pads of any substantial size.

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Re:A hacker stole $31M of Ether – how it happened, and what ... by dsacco on Friday July 21, 2017 @12:23AM (#14818051)
> Formally, the condition isn't "never use a one-time pad with the same key numbers" it's "make sure the key numbers of each pad are statistically independent of each other".

And to expand on this - this is why it is imperative that a source of true randomness is used as a seed. Pseudorandomness cannot (by definition) satisfy statistical independence.

If you don't have a source of true randomness, you've just implemented a stream cipher, not a one-time pad.

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