Something they will have to think about the day that there are IPv6-only services. Which is not today or anytime soon.

Well, I've seen several. Nothing for the general public. But things like the CMS/admin interface of a big web site. The site itself is on v4, the admin interface not.

> Something they will have to think about the day that there are IPv6-only services. Which is not today or anytime soon.

Let me guess, you live in and/or operate setups in the US?

Yeah, the US has disproportionately many IPv4 addresses.

Meanwhile if one of our services doesn't need IPv4, it doesn't get IPv4. And if it does need IPv4, it's increasingly common to be IPv6 behind an IPv4 reverse proxy.

And as a result, due to the extra reverse proxy, you'll increasingly just get worse performance on IPv4 than native IPv6.

What you call the "extra reverse proxy" is cgnat and cgnat doesn't add more latency than any other host in the path to the destination server.

It's called CGNAT when you do it near the end user / eyeballs and do it generically for all services on the internet.

When you do it near the service being provided, and only for your own services, it's called a Reverse Proxy.

You are right that these two things are similar, but they aren't identical; CGNAT attempting to handle you trying to talk to who knows what on the Internet (e.g. game servers, VoIP) is a much harder problem to solve than a Reverse Proxy handling a known set of protocols you want to expose.

And, yes, an unloaded CGNAT or Reverse Proxy is not noticable in terms of performance. However, both of them have load limits where you need to scale them up, and particularly CGNAT frequently degrades (due to larger tracking tables) before completely falling over.

There were (haven't checked for awhile) very cheap vps offerings that come only with ipv6 with no possibility to obtain ipv4 at all. While not useful for typical stuff, I've successfully used a swarm of these for personal project. I expect these things to become more common as companies like ovh start charging $10+ for a small fallback ipv4 address range.

IoT networks come to mind. There is nothing like 6LoWPAN for IPv4

My VPS provider has a cheaper tier with v6 only. Though I imagine you'd only use that for running little utilities which aren't publicly accessible.