Re-reading https://apenwarr.ca/log/20170810 https://apenwarr.ca/log/20170810 (linked elsewhere in this thread as well), right the thing that should have been so

Re-reading https://apenwarr.ca/log/20170810 https://apenwarr.ca/log/20170810 (linked elsewhere in this thread as well), right the thing that should have been solved first as the introduction of a TCP and UDP replacement suite that could handle mobility, since then switching IP versions at layer 3 would be much easier. But 30 years ago mobility wasn't as critical as 20 years ago and the IETF didn't foresee it. Also, introducing new transport protocols is quite difficult due to middleboxes -- at least that was the experience with SCTP, but a TCP that solves mobility would probably lead to middleboxes getting fixed quickly.