I came across this 1979 paper by P.M. Lu from Bell
Labs Naperville
Full paper is available here:
https://www.computer.org/csdl/pds/api/csdl/proceedings/download-article/12O…
I do not know what RIDE was and if its approach
qualifies as a FSS precursor. Maybe it is like 'Unix United / Newcastle
Connection' in its approach.
Indeed it appears to have been like the (later) Newcastle Connection in its approach.