It’s not _that_ different. Larger address space, more emphasis on multicast for some basic functions. If you understand those functions in IPv4, learning IPv6 is very straightforward. There’s some footguns once you get to enterprise scale deployments but that’s just as true of IPv4.

> The current adoption woes are exactly because IPv6 is so different from IPv4. Everyone who tries it out learns the hard way that most of what they know from IPv4 doesn't apply.

In my experience the differences are just an excuse, and however similar you made the protocol to IPv4 the people who wanted an excuse would still manage to find one. Deploying IPv6 is really not hard, you just have to actually try.

Part of the ipv6 ambition was fixing all the suboptimally allocated ipv4 routes. They considered your idea and decided against it for that reason. But had they done it, we would've already been on v6 for years and had plenty of time to build some cleaner routes too.

I think they also wanted to kill NAT and DHCP everywhere, so there's SLAAC by default. But turns out NAT is rather user-friendly in many cases! They even had to bolt on that v6 privacy extension.

> I disagree. The current adoption woes are exactly because IPv6 is so different from IPv4.

How is IPv6 "so different" than IPv4 when looking at Layer 3 and above?

(Certainly ARP vs ND is different.)

But that is a bug in history. IPv6 was standardized BEFORE NAT.

“most what they know from IPv6” is just NAT.

> A less ambitious IPv4 is exactly what we need in order to make any progress

but we’re already making very good progress with IPv6? Global traffic to Google is >50% IPv6 already.