Stanford University Network workstation. I have seen
some documents
about it on
stacks.stanford.edu, but I don't remember about the
software. In some versions, it's a more of a multi-head remote graphics
terminal, so maybe not Unix.
In the 1980 document, it's described as a single 68000 serving up to 16
seats. "only the basic Pup Telnet protocols need be implemented on the
workstation's MC68OOO processor. The SUN terminals could then be
programmed to emulate currently available terminals, such as Datamedias,
Telerays, Tektronix 4014 graphics terminals, or III displays."
https://stacks.stanford.edu/file/druid:gg867qx3134/gg867qx3134.pdf
But by 1982 it looks much like a classic workstation. "The SUN Memory
Management Unit has been designed to support a multitasking operating
system such as Bell Lab’s UNIX."
http://i.stanford.edu/pub/cstr/reports/csl/tr/82/229/CSL-TR-82-229.pdf