The people supporting TCP/IP had a head start and out-executed the OSI committees and it wasn’t even funny.
The people supporting TCP/IP had a head start and out-executed the OSI committees and it wasn’t even funny.
Another one of the "well-done in theory, but left in the dust by reality" approaches: X.25.
But IETF, with their emphasis on practicality, on "rough consensus and running code", was far more on the agile end of the spectrum than OSI was. IETF would recognize a problem, have an RFC, and have working implementations before OSI had done anything. This meant that if you wanted something, your first chance to get it (often by years) was on the IETF road, not on the OSI road. Repeat that a bunch of times and the people who could benefit from new things all moved to the IETF standards.
Then the next (?) year there was access to the "PAD" (Packet Assembler Disassembler) to JANET, from which one could issue a command to connect to an X.25 address. I still remember the number of NSFNet relay, 00004001018057 [1], which in turn allowed you to telnet to other internet services. I think I logged into Nyx and a few other BBS-like things.
Then I did an industry year at ICL, a British computer company long-since engulfed by Fujitsu, where they were also X.25 focused for big networks and Novell Netware focused for small networks - but the web was starting to be a big deal and I couldn't get anyone to listen. I have an anecdote about downloading the SLS Linux distro via an archive re-mailer that I won't bore you with right now :)
Then, in my final year back at the university, the web seemed to explode and the X.25 stuff had more or less disappeared.
In retrospect it's amazing how quickly this changeover happened, even if it had been bulbbing away in the background for a long long time. From my perspective the WWW looked like the catalyst that pushed everything in favour of TCP/IP.
[1] If I remember rightly, the adjacent address 00004001018056 was another Vax somewhere that hosted a bunch of LaTeX stuff?
Then people who went to school in the late 80s took that to $WORK in the early 90s, and by the mid-90s everything that wasn't TCP/IP had died. Novell's IPX, for example, was a thing still in the mid-90s, but a dying thing. Winsock for Windows 95 was the last thing that was needed to make TCP/IP rule -- after that there was just no way to do anything but TCP/IP.
It was a matter of network effects.