Ray Soucy wrote:
Sounds like we have one group saying that IPv6 is too complicated and that all the "overhead" of IPv6 had resulted in slow adoption.
Meanwhile we have others saying it doesn't have enough functionality, and should also include IGP.
Not at all. It is wrong that ND is so complicated that it even act as IGP proxy. To simplify the situation, let separate address resolution and IGP, which is the conventional wisdom of IPv4. ND became too complicated unnecessarily trying to offer incomplete and incorrect assistance from routers to nodes, even though the nodes should take care of themselves using information provided through IGP. Having a default router is fine if there is only one router. However, with multiple routers, default routers and ICMP redirects are nothing more than an incomplete proxy of IGP.
There is a lot of academic and theoretical argument being made here, but not so much on the practical application side.
Though NANOG may not be a good place to discuss about practical application side, it may be helpful to mention IPv6 is totally broken for the side. That is, as the length of IPv6 extension headers is unlimited and there are extension headers inserted automatically without application control, there is no guaranteed minimal payload size left for the transport layer. As PMTUD of IPv6 is proven to be inoperational: http://meetings.apnic.net/__data/assets/file/0018/38214/pathMTU.pdf we must assume MTU of 1280B. But, as IPv6 extension headers can be as lengthy as 1000B or 2000B, no applications are guaranteed to work over IPv6. Masataka Ohta