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UUID to the rescue. https://en.wikipedia.org/wiki/Universally_unique_identifier

It:

- is a standard

- adoption is widespread in computing platforms

- addresses the birthday problem (in v4, chances of a collision in a 103 trillion set is 1 in a billion)

The UUID scheme uses random digits. The article states that 19 random decimal digits (about 63 bits) yields a collision probability of 96%. More digits lowers the probability of collision to 0.0003% at 25 decimal digits (83 bits).

So yeah, UUID is great, but only because it uses 128 random bits, which is pretty much exactly along the lines of what the article is asserting.

Pedantic, but UUID v4 (which is the random one) only has 122 bits of randomness, 6 bits are used to identify the version and variant.

https://en.wikipedia.org/wiki/Universally_unique_identifier#...

> addresses the birthday problem (in v4, chances of a collision in a 103 trillion set is 1 in a billion)

Does that mean if you randomly assign ID numbers to 8 billion people you’d get 8 collisions?

It means that if you were to assign an ID to 103 trillion objects a billion times, the average amount of times you would get a collision at all is 1.

Reply on news.ycombinator.com