Earlier quoted context omitted.
With IPv6 it's plausible that you can avoid collisions as long as you use an expensive hash function, but for v4 how do you avoid IP collisions? With only 22 bits of entropy in your v4 addresses, you'll get accidental collisions with only ~2000 users.
Indeed. So what we do is build your ipv4 using private key bits + collision_index. It is not perfect but it has worked in our tests. We'll keep improving it. The collision_index is incremented when a collision happens on a network. Let's say you join network A, B, C. But when you join C, another peer has the same IP. The coordinator (which is a role anybody can have in the network) will not accept you in the network…
(I really hope "private key" was a typo of "public key"?)