https://en.wikipedia.org/wiki/Absement#Applications

>It is gradually becoming acceptable to dismiss IPv6 and suggest searching for a modern, practically minded alternative. Important first step in untangling the mess.

>Naturally opinions vary as to what exactly would constitute modern. Common complaint is the significant mixing of OSI layers, in particular application level concerns like significant baggage of encryption & authentication. And then there's my pet peeve of BSD Sockets API incompatibility which was introduced accidentally.

https://news.ycombinator.com/item?id=37119627

IP reputation scoring is feasible with 4.3 billion IPv4 addresses.

That model breaks down when you’re dealing with 340,282,366,920,938,463,463,374,607,431,768,211,456 possible IPv6 addresses.