@anatoliyl It wasn't protocol version 11 yet by a long shot. The protocol changed very rapidly in the first few years and didn't really stabilize until version 10 in 1986, followed shortly thereafter by version 11 where commercial vendors (mostly DEC IIRC) had contributed enough production-quality code to make it more than just a research prototype, which I think was in late 1988, where it's been frozen ever since -- first by broad adoption and more recently by abandonment.