Ethernet won with one passive cable and let stations sort out collisions

In 1976 Robert Metcalfe and David Boggs of Xerox PARC published Ethernet: Distributed Packet Switching for Local Computer Networks in the Communications of the ACM. Their design rejected redundant connections and dynamic routing: we choose to achieve reliability through simplicity, with a shared, passive broadcast medium and no central control.

Stations broadcast packets onto a branching coaxial cable; simultaneous transmissions collide, and each station backs off for a random interval that adapts to load, keeping utilization near optimum. Because the medium is passive and tapping a cable is cheap, adding a station costs almost nothing, the opposite of a star network where every connection requires central switching.

Xerox published the design widely: its PARC report CSL-80-2, The Ethernet Local Network: Three Reports (February 1980), reproduced the 1976 paper plus design and performance studies so others could build the system. The approach defined local networking: the IEEE 802.3 Working Group, which develops standards for Ethernet networks, descends directly from this design.

Share one passive wire; collide and retry

A passive shared medium made the marginal cost of a new station nearly zero.

Distributed contention needed no central switch, so there was no single point of failure or cost.

Publishing the design let other vendors build compatible systems and carry it into standards.

A design whose incremental cost per user falls, a shared passive medium instead of a switch per connection, wins on price. Publish the spec and the ecosystem builds itself.

Ethernet became the world's dominant local-network technology. The IEEE 802.3 Working Group continues to develop the Ethernet standard family, and the core ideas from the 1976 paper, a shared medium, distributed arbitration and collision recovery, shaped a half-century of networking hardware and remain in the standards' DNA.