> Now imagine that X changes addresses to Q. It still sends out packets tagged with (uuid,80), to IP address Y, but now those packets come from address Q. On machine Y, it receives the packet and matches it to the socket associated with (uuid), notes that the packets for that socket are now coming from address Q, and updates its cache. Its return packets can now be sent, tagged as (uuid), back to Q instead of X. Everything works! (Modulo some care to prevent connection hijacking by impostors.2)

And how the fuck anything in-between knows where to route it ? The article glows a blazing beacon of ignorance about everything in-between.

The whole entire problem with mobile IP is "how we get intermediate devices to know where to go?" we're back to

> The problem with ethernet addresses is they're assigned sequentially at the factory, so they can't be hierarchical.

Which author hinted at then forgot. We can't have globally routable, unique, random-esque ID precisely because it has to be hierarchical. Keeping connection flow ID at L4 instead of L3+L4 changes very little, yeah, you can technically roam the client except how the fuck server would know where to send the packet back when L3 address changes ? It would have to get client packet with updated L3 address and until then all packets would go to void.

But hey, at least it's some progress ? NOPE, nothing at protocol layer can be trusted before authentication, it would make DoS attacks far easier (just flood the host in a bunch of random uuids), and you would still end up doing it QUIC way of just re-implementing all of that stuff after encryption of the insides