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Comment by keybits | Hacker News Reader

Tailscale have a great FAQ about IPv4 vs IPv6: https://tailscale.com/docs/reference/faq/ipv6

If you're not an expert in this area it's worth a read - I certainly learned a few things!

> IPv6 doesn't make it easy to allocate subnets to every device on a LAN; instead, subnets might be delegated to your local router, and then only individual addresses allocated to each device. If one of those devices then wants to route traffic on behalf of other devices (for example, to a sub-subnet behind a router, where the upstream router doesn't cooperate), it will need to use NAT. For example, this is how Tailscale exit nodes work, even with IPv6.

This is quite wrong, there'd DHCPv6-PD (prefix delegation) specifically designed to do this. Even more interestingly, it has recently been made part of IETF CPE requirements (RFC 9818 update to RFC 7084, July 2025).

That was excellent, thanks for recommending it. I particularly liked how it's a pretty factual FAQ, not particularly cheerleading for IPv6 nor saying "IPv6 is a failure, give up on it".

Here is my article that I wrote when I wanted to learn more about IPv6: https://ssg.dev/ipv6-for-the-remotely-interested-af214dd06aa...

EDIT: After reading Tailscale's article, I noticed that I overlooked our neverending dependence to NAT despite that IPv6 seems to eliminate it.

interesting read, pretty depressing take if you're pro IPV6. I think their guess that IPV6 has low value-add when considered as part of a hybrid environment is probably one of the better explanations I've heard for poor uptake.

The linked post are also interesting reads:

https://tailscale.com/blog/two-internets-both-flakey

https://apenwarr.ca/log/20170810

a great assessment thanks I hadn't seen that

"IPv6 is the next generation of the Internet Protocol (IP), the successor to IPv4."

This is a misconception. It is not the successor to IPv4, it is an alternative. Maybe the alternative is so good it will eventually make the older extinct, but it does not look like that

I agree with you. While I can see some benefits to v6 on the internet, I find v4 to be miles easier and cleaner to work with in a LAN setup. Unfortunately though v6 oversteps on LAN features and makes bridging v4 and v6 way uglier than it should.

> v6 oversteps on LAN features and makes bridging v4 and v6 way uglier than it should

How so?

Regardless of whatever other things may be better or worse about ipv6, it's still a reality that as we continue connecting more and more devices to the internet eventually ipv4 addresses will become so scarce and valuable that a not-insignificant minority of residential customers will be behind such aggressive CGNAT that the internet will become nearly unusable unless a majority of the services they are using support ipv6.

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