The biggest thing is all the v4 addresses are no longer valid in v6. They had a choice and went with making a separate parallel network with new routes. This means DNS DHCP etc work similarly but are completely different, and the separation between DNS v4 and v6 of course is never clear in any router UI, network config file, etc. And the routes themselves are different.
SLAAC itself isn't complicated, but it means introducing multiple kinds of addresses, which is complicated. Privacy addresses were the latest thing. The history of this has left the defaults in a wacky state, like I got a new router and idk what to expect if I enable v6 on it. Even disabled v6 on my laptop cause idk what it'll do when I join someone else's network. Default should've just been DHCP+NAT from the start, not a loaded gun aimed at foot.
And SLAAC means random addresses that are human-unreadable. "Just use DNS" but nah, nobody will do that.
::203.0.113.42 (tunnels to 203.0.113.42 over v4)
::ffff:203.0.113.42 (opens a v4 connection via an AF_INET6 socket)
64:ff9b::203.0.113.42 (translates to v4 at nearest NAT64 point)
What are these then? Also, it's not like they had a choice here. v4 is hardcoded to 32 bits, so the option of making a single network with a bigger address size wasn't available.
I think I can count that as falling under both "something it already does" and "something that's impossible".
Your laptop will just get some IPs as appropriate for the network it's on, and then it'll use them. You don't need to think hard about it.
SLAAC itself isn't complicated, but it means introducing multiple kinds of addresses, which is complicated. Privacy addresses were the latest thing. The history of this has left the defaults in a wacky state, like I got a new router and idk what to expect if I enable v6 on it. Even disabled v6 on my laptop cause idk what it'll do when I join someone else's network. Default should've just been DHCP+NAT from the start, not a loaded gun aimed at foot.
And SLAAC means random addresses that are human-unreadable. "Just use DNS" but nah, nobody will do that.