Anonymous rate limits for us are skewed towards preventing abusive behavior. Most users do not have a problem, even there is a CGNAT on IPv4.

For IPv6, if we block on /128 and a single machine gets /64, a malicious user has near infinite IPs. In the case of Linode and others that do /64 for a whole data center, it's easy to rate limit the whole thing.

Wrong assumption or not, it is an issue that is made worse by IPv6

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GoblinSlayer 11 minutes ago | parent | next [-]

If a single machine gets /64 and you rate limit by /64, what doesn't work?

>Linode and others that do /64 for a whole data center

That's how it's supposed to work.

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agwa 2 hours ago | parent | prev [-]

I don't doubt your experience, but I wouldn't expect it to continue. I don't think Tuna-Fish is correct that "most" of the IPv4 world is behind CGNAT, but that does appear to be the trend. You can't even assume hosting providers give their subscribers their own IPv4 addresses anymore. On the other hand, there's a chance providers like Linode will eventually wise up and start giving subscribers their own /64 - there are certainly enough IPv6 addresses available for that, unlike with IPv4.

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Tuna-Fish 38 minutes ago | parent | next [-]

> I don't think Tuna-Fish is correct that "most" of the IPv4 world is behind CGNAT

~60%+ of internet traffic is mobile, which is ~100% behind CGNAT.

On desktop, only ~20% of US and European web traffic uses CGNAT, but in China that number is ~80%, in India ~70% and varies among African countries but is typically well over 70%, with it being essentially universal in some countries.

Overall, something a bit over 80% of all ipv4 traffic worldwide currently uses CGNAT. It's just distributed very unevenly, with US and European consumers enjoying high IP allocations for historical reasons, and the rest of the world making do with what they have.

	▲	agwa 6 minutes ago \| parent [-]
		Oh wow, thanks for those numbers! Since mmbleh mentioned Linode I'm guessing they're more concerned with traffic from servers, where CGNAT is uncommon. But even that may be changing - https://blog.exe.dev/ssh-host-header

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mmbleh an hour ago | parent | prev [-]

Yeah, absolutely no expectations for the future. My point was more that while there may be clear benefits for users, IPv6 presents real problems for service operators with no clear solutions in sight.

Given that GitHub also offers free services for anonymous users, I can imagine they face similar problems. The easiest move is simply to just not bother, and I can't blame them for it.