Similarly for direct comparison, ULID has 48-bit timestamps, also at the millisecond, and 80 random bits. Also to compare, the ULID spec technique for monotoni

Similarly for direct comparison, ULID has 48-bit timestamps, also at the millisecond, and 80 random bits. Also to compare, the ULID spec technique for monotonicity is to take a single random value and then start incrementing the lowest bits, trading random entropy for direct "nearness", one after another. Versus the rand_a approach is effectively using the most significant bits, but keeping more random entropy.