@sphcow

my first job out of the service was at a place doing OSI protocol conformance testing.

at the time, all the governments were pushing for OSI as the networking stack the world would use. TCP/IP was that weird free stuff they didn't trust. but they hit two problems:

the first was that lots of vendors supported TCP/IP on their gear. OSI support was nascent, twitchy, and not even available on lots of hardware.

the second problem was the real death knell of OSI. every vendor that did OSI had a "protocol conformant" implementation. but everyone discovered that the various vendors couldn't actually talk to each other or work on the same network.

what they thought they needed was protocol conformance. what they found they really needed was interoperability.

if you can't buy from multiple vendors and have a heterogenous network with everything working as expected, you don't have interoperability.

the quieter lesson that we're still learning is that if your protocol standard doesn't enable interoperability, it's a lousy standard.