Arista is just a few months from an exclusion of their products entering the USA

That constitutes an API or instruction set.

If vendors have to invent different command syntax to do the same thing, that is not really an invention, and it is bad for customers, and their choice. Complex configurations have to be transliterated from one language to another in order to migrate among equipment units.

This is like Lotus 1-2-3 versus Borland all over again: https://en.wikipedia.org/wiki/Lotus_Development_Corp._v._Bor...

"This case established that copyright does not extend to the user interface of a computer program, such as the text and layout of menus."

"Borland released a spreadsheet product, Quattro Pro, that had a compatibility mode in which its menu imitated that of Lotus 1-2-3, a competing product. None of the source code or machine code that generated the menus was copied, but the names of the commands and the organization of those commands into a hierarchy were virtually identical."

"Names of commands and organization of commands into a hierarchy:" same thing as the multi-word syntax in some Cisco box.

According to Cisco (specifically, their General Counsel):

"If infringement is found, Arista, despite their efforts to delay the ITC process, may be just a few months from an exclusion order banning a majority (or all) of their products entering the United States."

That's a (debatable) claim, not a fact, and -- for someone who works with gear from both of these vendors -- had me going "Huh!? What!?" and hurriedly clicking the link to get to the article to find out what was going on.

Regardless, I think this will be an important case. I don't know if Lotus v. Borland (as mentioned by kazinator) counts as precedent (though, I hope it does) but the decision will definitely affect future products and services.