Re: draft-arkko-ipv6-transition-guidelines WGLC

[Brian E Carpenter <brian.e.carpenter@gmail.com>]

On 2010-08-19 10:57, Cameron Byrne wrote:
...
> IMHO, traditional dual-stack is not viable for transition.  There are
> not incentives for me to dual stack at home, work, or while mobile.
> Traditional dual-stack does not provide a better user experience and
> it does not save me any IPv4 addresses.  Dual-stack + NAT44 may
> eventually have some benefits if I can by-pass the NAT44 with native
> IPv6.  Same can be said for DS-lite.  But, traditional dual-stack
> (public IPv4 and IPv6) is a non-starter.  And the idealistic notion
> that dual-stack leads to a future where eventually everything will go
> IPv6 and we can just turn off IPv4 without anyone knowing stopped
> being viable around 2005, transition time ran out and nobody deployed
> it.  

This, sadly, is true. The dual stack model assumed that IPv6
would get everyhwere before IPv4 exhaustion hit. Shame about
that. However, that does not preclude a model where an ISP
prefers to deploy dual stack routing and thereby ends up with
3 classes of customers
  - IPv4 legacy customers
  - dual stack customers
  - IPv6-only customers
Many ISPs might conclude that this was actually their best
option. Personally I think it's appropriate for the draft
to present this as the most obvious option, but probably
it should explicitly point out that the above three classes
of customers will exist as a result, and there will be
interoperability issues.

The draft says:

4.3.  IPv6-Only Core Network

   An emerging deployment model uses IPv6 as the dominant protocol

I don't think we should be *recommending* this choice, or
any other choice, but the word "emerging" makes it sound
risky. Maybe we could just say "Another depolyment model..."

    Brian