1980

Commercially Available Ethernet

Robert Metcalfe (b. 1946), David Boggs (b. 1950), Chuck Thacker (1943–2017), Butler Lampson (b. 1943)

While working on his PhD thesis, Robert Metcalfe ran across a paper on the ALOHANET wireless computer network that had been developed at the University of Hawaii. Eager to find out more, he flew to Hawaii to learn from ALOHANET’s inventors.

Whereas ALOHANET sent data packets through the air, Metcalfe’s design sent radio frequency energy through coaxial cables that had multiple taps, one for each computer, and a “terminator” at each end. Called Ethernet, after the nonexistent “ether” that many 19th-century scientists thought was the medium through which light propagated, the network proved to be a simple, cheap, and fast way to connect computers within a room or a building—a local area network (LAN).

Although Metcalfe is sometimes called the inventor of the Ethernet, the actual patent was filed by Xerox, where Metcalfe worked during and after graduate school, with David Boggs, Chuck Thacker, and Butler Lampson listed as co-inventors. Metcalfe left Xerox in 1979 and formed 3Com®, which worked with DEC, Intel, and Xerox to make Ethernet a computing-industry standard. The Institute for Electrical and Electronic Engineers (IEEE) adopted Ethernet as the IEEE 802.3 standard in June 1983.

The Ethernet standard specifies both the physical connection between computers and the logical structure of the packets that the network carries. But Ethernet doesn’t specify the higher-level network protocols. As a result, DEC and Xerox invented their own network layers—DECNet and XNS (Xerox Network Systems). All of these proprietary networking technologies eventually lost out to Internet Protocol (IP) running over Ethernet.

By the end of the 1980s, companies were introducing versions of Ethernet that could run over twisted-pair wiring instead of coaxial cable. Eventually standardized as 10Base-T, twisted pair dramatically reduced wiring costs and increased reliability, because each computer had its own wire that led back to an Ethernet “hub.” The original Ethernet ran at 10 megabits per second, but in 1995 so-called “fast Ethernet” running over twisted pair at speeds of 100 megabits per second was introduced, followed by a gigabit in 1999, and 10 gigabits per second (running over optical cables) in 2002.

Ethernet cables and network switches.