But the main uses were sending jobs to printers and reaching Arpanet via an early router and long-distance lines. Evolution was gradual: Laser printers came in 1974 and email around 1976, Metcalfe said.
Throughout the 1970s, the use of Ethernet expanded, but only around Xerox facilities and a few other institutions, such as Stanford and MIT, where cutting-edge computing research was being done. The White House also got Ethernet, along with some Altos that Xerox donated.
For a time, Xerox was preparing to sell Ethernet as a commercial product, called The Xerox Wire, as part of a proprietary office system. But in 1980, the company instead proposed it to the Institute of Electrical and Electronics Engineers as an open standard. In the intervening years, other companies had come up with their own LAN schemes, so there were many other approaches in play around the industry. In the end, the IEEE designated three as standards: Ethernet, IBM's Token Ring and a system from General Motors called Token Bus.
Though GM's entry didn't go far, Token Ring and some other LANs, including ARCnet, survived.
"We then spent a few years killing each other, and eventually Ethernet won," Metcalfe said. "But it was a long eventually."
By the late 1980s, Ethernet had effectively won, Metcalfe said. Its backers had included Intel, Digital and a small company Metcalfe himself launched to serve the nascent market for adapters and network gear, called 3Com.
PARC's team had taken Ethernet up to 20Mbps, but to ensure it would work on Intel's chips, they scaled back the proposed standard to 10Mbps. Still, they weren't sure anyone would need that much speed. Eventually people did need that much Ethernet, and then some.
"We argued about whether 10 was too much. And then came 100Mb, and then a gigabit, and then 10Gb and 40Gb, and now 100Gb, and now 400Gb is being standardized, and terabit is being talked about," Metcalfe said. "The big surprise has always been that new applications emerged each time we sped up Ethernet."
As with other widely used technologies, success has bred more success. Each iteration has gotten cheaper as it's grown more ubiquitous. One key to Ethernet's success is that every successive version has been backward compatible with the previous ones already in use, Metcalfe said.
Metcalfe shares the patent for Ethernet with Boggs, as well as Thacker and Butler Lampson, another PARC guru. Many others at PARC helped develop software and hardware for the new network, he said. Today, Metcalfe teaches at the University of Texas at Austin and says he's winding down a career as a venture capitalist at Polaris Partners. Boggs co-founded LAN Media, a maker of network adapters, which was acquired by SBE in 2000.
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