On Wed, Oct 11, 2023 at 1:53 PM Mark Andrews <marka@isc.org> wrote:
> On 12 Oct 2023, at 06:51, Delong.com <owen@delong.com> wrote:

> The point here is that at some point, even with translation, we run out of IPv4 addresses to use for this purpose. What then?

You deliver the Internet over IPv6.  A really large functional Internet exists today if you only have IPv6.  It is only getting bigger.  Lots of (the majority?) of CDNs deliver content over IPv6.  Lots of companies outsource their SMTP to dual stacked service providers so that email still gets through.
After 20 years there is no excuse for ISPs failing to deliver IPv6.  If you have to you, outsource your NAT64, DS-Lite transition service to someone that has IPv4.  I’m surprised that it isn’t common today.

While you claim "there is no excuse for ISPs failing to deliver IPv6", the reality is that many ISPs don't support fully functional IPv6 deployments.
There are far too many networks that allocate a single /64 for a wireless customer, and ignore DHCPv6-PD requests.  There's a reason that IPv6-relay functionality in OpenWRT is so widespread--because even when ISPs "support" IPv6, they often do so poorly, leading to awkward hacks like relaying the same /64 downstream through intervening routers.
I'm all for the eventual success of IPv6, but at the moment, we're really not there.

But the bigger point is that there's still big chunks of the content side that aren't reachable via IPv6.
https://www.6connect.com/blog/ipv6-progress-report-top-sites-2019/ 
http://www.delong.com/ipv6_alexa500.html
https://whynoipv6.com/

That last report shows that only half of the top 1000 websites on the Alexa ranking support IPv6.  So we're a long way away from being able to simply say "You deliver the Internet over IPv6."

Your last two sentences are exactly what I stated as a business proposition earlier.  You said (fixing the typos):
"If you have to, you outsource your NAT64, DS-Lite transition service to someone that has IPv4.  I’m surprised that it isn’t common today."

In a world where only half the content sites are reachable via IPv6, and IPv4 address space is exhausted, that requirement to outsource NAT64 functionality is becoming more and more a business reality going forward.

Can you list any company today that provides an outsourced NAT64 translation service?
The only one I'm aware of is the one Kasper Dupont is running, and he's got a very clear warning that it's not suitable for high-volume use.

I can't help but see an up-and-coming demand for services to fill this need, as it's clear Kasper's setup isn't going to handle the load for all the IPv6-only networks that decide there's actually content they want to get to in the other half of the Alexa top 1000 sites that don't support IPv6.  I'm enjoying being retired, but seeing a future demand with nobody stepping up to fulfill that demand is almost enticing enough to be worth un-retiring for to build out...

Thanks!

Matt