Yes, I meant IPv4.
And rate limiting is very uncertain. If I limit per /56, users that have an entire /48 can outright bypass the rate limit. If I limit per /48, maybe I'll erroneously limit thousands of users whose ISP has all of them on the same /48.
Don't you have those same issues with banning/rate limiting IV46 though?
The difference between a /48 (like my residential handoff) and a /64 (like some people get) is the same as a difference between blocking a single /32 ipv4 address and blocking an entire /16 - which is a very large allocation
If you wanted to block me, you'd have to block the whole /48. If you blocked a /48, you could be blocking 64,000 people.
I meant IPv4 - one IP might represent thousands of users.
Looks like crote brought the issue up in a sibling thread.
I haven't experienced such congested CGNATs. And assuming there are people who are under such CGNATs, they are probably used to being rate limited all the time.
But the exact same issue exists with IPv4 due to CGNAT? A single IPv4 address could be used by a single user, or their ISP could be sharing that same single IP with many thousands of users.
Users aren't getting single IPv6 addresses though. Most assign a /48 which is at least a bit better.