jimbocoin on Nostr: There are plenty of ways of assessing if a specific bit stream is “random”. It ...

There are plenty of ways of assessing if a specific bit stream is “random”. It basically comes down to measuring diversity of values and looking for patterns.

The simplest check is “all zeros” or “all ones”. Those are obviously non-random at the scale of a Bitcoin seed (128 bits plus).

But a repeating pattern is also non-random. So alternating zeros and ones (“010101010…01”) is also obviously non-random as is other alternating patterns (“00110011…0011”).

The problem in the ColdCard case is that all of the seeds they produced would have passed these checks. The problem wasn’t in the diversity of zeros and ones in the seeds, or patterns resident within a specific seed.

The problem was the distribution of seeds. No local check on the produced values can assert a global problem like that. The only way to detect that class of problem is by auditing the code, which no one sufficiently did until now.