On 9 feb 2011, at 20:53, William Herrin wrote:
* Carrier NAT buys us enough years to build an IPv4 successor
You're kidding, right? How long did it take exactly to get where we are now with IPv6? 18, 19 years? And yet there's still all kinds of stuff that isn't really ready for prime time yet.
* Next protocol should really be designed to support interoperability with the old one from the bottom up. IPv6 does not
That's because it's not the headers that aren't incompatible (the protocol translation is ok even though it could have been a bit better) but the addresses. A system that knows about 32-bit addresses will just not talk to a system with a 128-bit address. Once we're at 128-bit addresses then we can migrate to IPvA (7 - 9 are already taken) without much trouble. But then, 32-bit ASes interoperate with 16-bit ones with no trouble and still after a decade the support for that is not nearly good enough, either.