This. It will break a lot of existing applications, devices, firewalls, and have conflicts with companies that are somewhat already using them in a public or pr

This. It will break a lot of existing applications, devices, firewalls, and have conflicts with companies that are somewhat already using them in a public or private environments. And if we want to do it anyway despite all the trouble, it will only push forward the problem a few months or years. In the other hand, IPv6 is already used by nearly half of internet, and probably most installed infrastructure supports it. And it have a lot of advantages over IPv4, starting with not having to use NAT.