Re: [v6ops] I-D Action: draft-ietf-v6ops-ula-usage-recommendations-02.txt

[Lorenzo Colitti <[e-mail]>]

On Thu, Feb 20, 2014 at 10:35 AM, Mark Andrews <[e-mail]> wrote:

> > How are they punished? And what will they do when they are punished? I
> > guarantee that renumbering will not be the solution, NAT will be the
> > solution.
>
> Both sites just generate a NEW ULA prefixes.  They can continue to
> use the collision prefix until the heat death of the universe if
> they wish to or they can migrate to the new prefix.  IPv6 is NOT
> IPv4.  Running parallel prefixes is *standard* proceedure.  They
> just need to talk to each other using the NEW prefixes which should
> be no more complicated than pushing new address selection tables.
>

No, sorry. One of the main reasons people are advocating ULAs here is
"because we'll have stable space and will never have to renumber!!11". Once
you buy into that mantra, you'll be hardcoding IP addresses into
configuration again, exactly like we do in IPv4 today. And exactly like in
IPv4 today, renumbering will be prohibitively expensive.

As for multiple ULA prefixes... again, I think you're ignoring the
realities of corporate IT staffing, corporate IT systems, and vendor
capabilities.

I think it's obvious that the path of least resistance (and thus, the
solution that most admins would choose) will be NAT/NPT. After all, if you
want to use ULAs to talk to the outside world (And why wouldn't you, right?
It's what we do in IPv4, right?), you have to do NAT or NPT anyway.