[Dagger2]

But v6 _is_ backwards compatible though? It's got dual stack, Teredo, 6to4, 6rd, 6over4, ISATAP, 6in4/4in6, NAT64/DNS64, 464xlat, DS-lite, MAP-T/E, 4rd, LW4over6... how is this not backwards compatible? You could make a reasonable argument that it has too many backwards compatibility methods, even.

> The “you don’t have to use NAT anymore” is great theoretically, but it renders a lot of casual network maintainers mental model of network security obsolete without a clear and simple alternative

If your mental model of security relies on NAT then your mental model was wrong, and obsoleting it was the right thing to do.

If v6 made you realize this, then it seems it's more intuitive than v4+NAT was for you.