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Robert Metcalfe

b. 1946 Tier III

The Harvard reject who wired computers together and predicted their doom

Portrait of Robert Metcalfe — Andreu Veà, WiWiW.org — 2004 — CC BY-SA 3.0 via Wikimedia Commons

Robert Metcalfe grew up on Long Island, the son of a gyroscope technician and a school secretary, and graduated from the high school where his mother worked. He collected two bachelor's degrees from MIT in 1969, in electrical engineering and industrial management, then went to Harvard for a master's and a doctorate. Harvard rejected his 1972 thesis outright — he was, in his own words, thrown out on his ear — because it leaned on a network, ARPANET, that MIT had refused to let him connect to campus. He took a job at Xerox PARC instead, found a paper on the University of Hawaii's ALOHAnet, fixed flaws he spotted in it, folded the fix into a rewritten thesis, and finally collected his PhD in 1973.

At Xerox PARC in 1973, Metcalfe and David Boggs built Ethernet, a way of wiring computers together over a shared cable so they could all talk without a central switchboard. He dated its birth to a May 22 memo he circulated; Boggs preferred November 11, the day the system actually worked. In 1979 Metcalfe left PARC and started 3Com out of his Palo Alto apartment to sell the technology commercially, and Ethernet went on to become the standard almost every wired network still runs on. The board eased him out as CEO in 1990. He spent the next decade writing a technology column, then became a venture capitalist and, from 2011 to 2021, a professor at the University of Texas at Austin. In 2023 the Association for Computing Machinery gave him the Turing Award, fifty years after that first memo.

Metcalfe's most famous public appearance has nothing to do with Ethernet. In 1995 he predicted the internet would suffer a catastrophic collapse the following year and promised, in print, to eat his words if he turned out to be wrong. He was wrong — 1996 came and went without a collapse — and in 1997, on stage at a World Wide Web conference, he made good on it, feeding a printed copy of his own column into a blender with some liquid and drinking the result in front of the audience. The board that eased him out of 3Com in 1990 had already made a related point more quietly: the engineer whose invention built the modern network had been judged, by the people running his own company, not the one to keep running it.

Metcalfe returned to MIT in 2022, fifty-three years after he left it, as a research affiliate in the same computing world where his career started. The technology he built in 1973 quietly won: wired Ethernet still carries most of the world's data traffic underneath the wireless networks people actually see, and Metcalfe's Law — his rule that a network's value grows with the square of its users — became a stock phrase in Silicon Valley pitch meetings, cited by people who have never heard of Xerox PARC. The Turing Award finally arrived in 2023, half a century after the invention. What lasted was the plumbing, not the fame that came with predicting its collapse.

Lifespan

15401700180019002030

Robert Metcalfe's life against the full span of the corpus — the fading end marks a life still in progress.

Notable works

Ethernet invention
Co-invented with David Boggs at Xerox PARC 1973
3Com Corporation company
Founded to commercialize Ethernet networking equipment 1979
Packet Communication article
His Harvard PhD thesis, revised around ALOHAnet research after an initial rejection 1973
Metcalfe's Law discovery
Describes a network's value as growing with the square of its users 1980

Life in brief

with age at each point

April 7, 1946 aged 0 Born in New York City
1969 aged ~23 Earns two BS degrees from MIT
1972 aged ~26 Harvard initially rejects his PhD thesis
May 22, 1973 aged 27 Circulates the "Alto Ethernet" memo at Xerox PARC
November 11, 1973 aged 27 The Ethernet system functions for the first time
1979 aged ~33 Co-founds 3Com in his Palo Alto apartment
1990 aged ~44 The 3Com board replaces him as CEO
April 1997 aged 50 Blends and drinks his printed internet-collapse prediction on stage
March 2023 aged 76 Receives the Turing Award for Ethernet