[knorker]

Wait, this person is in Denmark and can't change ISP?

If this happened to me then I'd change ISP. NAT on your home Internet? What is this, the US?

I thought if you were in Europe you'd pretty much always be able to get public IPv4, IPv6, and IPv6-PD. I know I can.

[BlueTemplar]

It's possible that he insists on IPv4 for some reason, though IMHO this is a bad idea and he should try everything to move to IPv6.

As you might guess, the ISPs that are forced to use CGNAT due to the lack of IPv4 addresses, are also the ones who tend to be the first on IPv6, for obvious reasons.

I know of a big ISP, a relative latecomer, infamous due to its CGNAT issues, who last summer boasted reaching 99% IPv6 coverage.

(And at the same time, for some reason they had to be forced by the government threats, that otherwise they would not be allowed to use 5G, to add opt-in IPv6 on cellular, which they did at the last moment last month...)

[XelNika]

CGNAT is standard for all smaller ISPs in Denmark. I'm not sure if it's mainly to stay competitive or due to limited supply, but they offer public IPv4 addresses upon request, sometimes for free. It makes sense really; if you default to CGNAT, which is fine for 99% of users, there will be more public addresses for the people who need them which keeps costs down for both segments. It's not the ISP's fault the standard is outdated.

[BlueTemplar]

I take issue that it's "fine for 99% of users" or that it's not a big deal :

https://news.ycombinator.com/item?id=25744675

[XelNika]

That is not a realistic scenario. Firstly, there's no waking up to find your server is unresponsive. It's part of the deal when you sign up. Secondly, public IPs are always an option. Thirdly, the ISPs I have used have always had relevant FAQ/help articles.

If any of those points do not apply to your ISP, that's not because of CGNAT, it's just a shit company. I've used four different ISPs in the past four years and getting rid of CGNAT has not been a problem once. IIRC only one of them used public addresses by default, two offered free dynamic IPs upon request and my current ISP offers paid static IPs for $3.

Tons of my friends and family have had CGNAT and never known. It's just not a big deal for most content consumers.

[Daho0n]

He can but instead he contacted his ISP and got it fixed, which is much better. I don't know which ISP he is using but sounds like it is on the awful (by Danish standards) TDC network. Good thing there's great fiber almost everywhere.

[msh]

TDC does not by standard use CGNAT, they give out dynamic IPv4.