Factors, actions influencing the possibility/timing of IDR for IPv6-based routing domains?

[Tom Vest]

Hi all,

Would be very grateful for assistance from list members.... apologies  
for any duplication...

I'm trying to compile a list of environmental factors or actions that  
might affect the probability and timing of direct participation in  
interdomain routing becoming practical, specifically for routing  
domains that start out with some IPv6 but without even one publicly  
routable IPv4 address.

The question I'd like help with is: what individual actions -- either  
undertaken directly by the aspiring IDR participant, or by the  
operators of other, established routing domains --  could directly or  
indirectly impact the probability, timing, and extent of this becoming  
generally possible?

Please note (if it wasn't already obvious) that I'm *not* talking  
about the possibility of becoming a pure/direct customer of another  
routing service provider, nor am I asking/making presumptions about  
IDR-related activities that are not commonplace, much less  
"guaranteed" for routing service providers in general (ubiquitous  
settlement-free peering, etc.). The basic idea is that there is a  
range of "normal" or "conventional" activities that operators of  
routing domains may choose to participate in today (e.g., exchanging  
traffic, indirectly or directly, potentially with most if all other  
routing domains; participating as a third party in traffic exchange  
between other routing domains -- aka providing transit; pursuing,  
accepting, and/or rejecting direct and indirect traffic exchange  
relationships; influencing traffic flows across those  
interconnections, etc.), none of which would be possible today for an  
operator of a pure IPv6-based (or any post-IPv4 runout) routing  
domain. The question is: what's going to change that?

My current provisional list of things that might incrementally change  
that includes:

1. New entrant(s) obtain an independently routable quantity of IPv4  
from someone/somewhere, which can be used to mediate traffic exchange  
between internal IPv6-based resources and external IPv4-based network  
elements.
2. Existing, IPv4-based routing domains offer native IPv6-based IP  
transit that is physically accessible by the aspiring new entrant(s).
3. Existing, Pv4-based routing service providers begin to accommodate  
incremental growth of existing and new customers using IPv6 *in a way  
that makes those new elements transparently reachable via native IPv6- 
based IDR.*
4. Existing, Pv4-based routing domains make some or all of their  
current, public-facing resources reachable via native IPv6-based IDR.

What else should be on the list? Additional comments, questions, or  
suggestions would be greatly appreciated!

Thanks in advance,

TV