[chuckadams]

tcp6 is a thing though, was created at the same time as ipv6, and it does have ports, along with udp6. But if you really want one ip per stream and just hardwire port 1 or something, it's not like IPv6 does anything to stand in the way of that. Mght have performance issues on some OS's binding thousands of IPs to one interface, but that's on them to fix. Bigger lift would be the APIs that would need to change to manage whole prefixes at a time instead of single IPs.

[pratyahava]

afaik tcp and udp are the same on top of ipv6 as they are on top of ipv4, there are no tcp6 and udp6, the "6" suffix just hints they are comminucated on top of ipv6, but the packets are the same as before, no new standards.

[chuckadams]

I could have sworn there was a different and simplified format for segments (datagrams are already about as simple as they can be), but I apparently had hallucinated it all these years. Turns out the only difference is using the larger addresses in the checksum algorithm.

Still, I do have to wonder about a port-free world. Seems a lot of things would get simpler.