[yuye]

If you've got Chunghwa/HiNet, you most likely don't suffer from CG-NAT. They're the most expensive offer because they're the best offer.

If you're with those shitty resellers, you 99% will get CG-NATed. You pay 50% of the CHT price, but you get 25% the quality. You see this in large apartment buildings: They take Chunghwa fiber and resell it, NAT the entire building into the 192.168.0.0/16 block to save on costs, because IPv4 is $$$. Forget about IPv6 support. The bandwidth they have is oversold, so the 400M you bought might not actually reach those speeds during peak hours, unless you're lucky enough to be living in a new building where more than half the apartments are vacant.

I have some experience with the latter. Their support staff is often utterly incompetent, too.

[consp]

This sounds like the solution the provider offered when they commercialised my student internet connection. A building with over 1k connections had 4 ipv4 adresses and no proper cgnat. This means you get niceties like:

* Everyone gets their neighbors favourite language in the search engine if you have a incognito session.

* Only about 32k sessions possible per adres. And yes you can claim them all and kill everyone's internet connection.

* All local ip's were interconnected and not firewalled. That was fun.

* You get banned or soft throttled everywhere due to "strange behaviour".

They were doing it on the cheap and fortunately got told it would void their contract if they did not provide something better and it was "fixed" after about a year. But during rush you would still end up maxing the 4gbit fiber uplink even with only a fast ethernet connection for everyone.