Vendor lineage
SynOptics - the other half of Bay Networks
Ethernet over telephone wiring, which turned a coaxial bus into something a building could actually be wired for.
SynOptics built structured wiring hubs that ran Ethernet over twisted pair, a Xerox PARC-derived idea that changed how buildings were cabled. Its 1994 merger with Wellfleet produced Bay Networks, joining the wiring business to the routing one.
The contribution is easy to undervalue now that twisted pair is simply what Ethernet runs on. Original Ethernet was a shared coaxial bus - one cable through a building, with every station tapped into it, and a single fault affecting everyone on the segment. Star wiring to a hub made the network diagnosable and the building wirable by electricians rather than specialists.
That is a recurring shape in this history: the technically interesting invention is the protocol, and the thing that makes it deployable is the wiring.