Robert Melancton Metcalfe

ACM A. M. Turing Award (2022)
ACM Grace Murray Hopper Award (1980)
2022 ACM A.M. Turing Award

ACM A. M. Turing Award

USA - 2022

citation

For the invention, standardization, and commercialization of Ethernet.

ACM named Robert Metcalfe recipient of the 2022 ACM A.M. Turing Award for leading the invention, standardization, and commercialization of Ethernet local-area networking technology. Metcalfe is Emeritus Professor of Electrical and Computer Engineering (ECE) at The University of Texas at Austin.

In 1973, while a Research Scientist at the Xerox Palo Alto Research Center (PARC), Metcalfe circulated a now-famous memo on May 22, 1973 describing a "broadcast communication network" for connecting some of the first personal computers, Altos, within a single building. The first Ethernet ran at 2.94 megabit per second, which was ~10,000 times faster than the terminal networks it replaced starting in 1973. Although the original design proposed implementing this network over coaxial cable, the memo envisioned "communication over an ether" making the design adaptable to any future innovation in media technology including legacy telephone twisted pair, optical fiber, radio, and even power networks, to replace the coaxial cable as the "ether". That memo laid the groundwork for what we now know today as Ethernet.

The Ethernet architecture was developed to address Xerox's need to connect 100 of the new Alto personal computers and their new laser printers. The original architecture was based on a single wire bus with a single transceiver per node, thus enabling a cost-effective design. The media access control in the Ethernet design incorporated Metcalfe's insights from his experience with Norm Abramson's RIP ALOHAnet. Metcalfe recruited David Boggs RIP to help build a 100-node Ethernet in two years. That first Ethernet was then replicated within Xerox to proliferate a corporate internet.

Metcalfe and Boggs' classic 1976 CACM article, "Ethernet: Distributed Packet Switching for Local Computer Networks," described the design of Ethernet. Metcalfe then led a team that developed the 10Mbps Ethernet, deployed internally at Xerox and forming the basis of subsequent standards.

After leaving Xerox in 1979, Metcalfe began consulting and laying the groundwork to ensure industry adoption of Ethernet. He succeeded as "marriage broker" when Xerox agreed to work with Digital Equipment Corporation and Intel (a consortium that became known as DIX), with the objective of making Ethernet an open standard. An IEEE committee ("IEEE 802") was formed to establish a local area network standard, and a slight variant of DIX became the "IEEE 802.3" standard, still vibrant today.

Metcalfe founded 3Com Corporation in June 1979. As the Internet was transitioning from dumb terminals to personal computers, 3Com debuted the first Ethernet interfaces for the IBM PC. Based on Metcalfe's technical leadership, 3Com democratized the Ethernet architecture and sharply reduced its cost as the Internet went viral.

In 2023, the 50th anniversary year of the invention of Ethernet, there are an estimated seven billion Ethernet ports active in the Internet. Ethernet was sufficiently general to allow an evolution in data rates by a factor of 100,000, today approaching a terabit per second. Today we take for granted Metcalfe's Ethernet invention as a large part of the Internet's lingua franca.

Press Release

ACM Grace Murray Hopper Award

USA - 1980

citation

For his work in the development of local networks, specifically the Ethernet

2022 ACM A.M. Turing Award

ACM has named Bob Metcalfe as recipient of the 2022 ACM A.M. Turing Award for the invention, standardization, and commercialization of Ethernet.

Metcalfe is an Emeritus Professor of Electrical and Computer Engineering (ECE) at The University of Texas at Austin and a Research Affiliate in Computational Engineering at the Massachusetts Institute of Technology (MIT) Computer Science & Artificial Intelligence Laboratory (CSAIL).

Invention of The Ethernet

In 1973, while a computer scientist at the Xerox Palo Alto Research Center (PARC), Metcalfe circulated a now-famous memo describing a “broadcast communication network” for connecting some of the first personal computers, PARC’s Altos, within a building. The first Ethernet ran at 2.94 megabits per second, which was about 10,000 times faster than the terminal networks it would replace.

Although Metcalfe’s original design proposed implementing this network over coaxial cable, the memo envisioned “communication over an ether,” making the design adaptable to future innovations in media technology including legacy telephone twisted pair, optical fiber, radio (Wi-Fi), and even power networks, to replace the coaxial cable as the “ether.” That memo laid the groundwork for what we now know today as Ethernet.

Metcalfe’s Ethernet design incorporated insights from his experience with ALOHAnet, a pioneering computer networking system developed at the University of Hawaii. Metcalfe recruited David Boggs (d. 2022), a co-inventor of Ethernet, to help build a 100-node PARC Ethernet. That first Ethernet was then replicated within Xerox to proliferate a corporate internet.

In their classic 1976 Communications of the ACM article, “ Ethernet: Distributed Packet Switching for Local Computer Networks ,” Metcalfe and Boggs described the design of Ethernet. Metcalfe then led a team that developed the 10Mbps Ethernet to form the basis of subsequent standards.

Standardization and Commercialization

After leaving Xerox in 1979, Metcalfe remained the chief evangelist for Ethernet and continued to guide its development while working to ensure industry adoption of an open standard. He led an effort by Digital Equipment Corporation (DEC), Intel, and Xerox to develop a 10Mbps Ethernet specification—the DIX standard. The IEEE 802 committee was formed to establish a local area network (LAN) standard. A slight variant of DIX became the first IEEE 802.3 standard, which is still vibrant today.

As the founder of his own Silicon Valley Internet startup, 3Com Corporation, in 1979, Metcalfe bolstered the commercial appeal of Ethernet by selling network software, Ethernet transceivers, and Ethernet cards for minicomputers and workstations. When IBM introduced its personal computer (PC), 3Com introduced one of the first Ethernet interfaces for IBM PCs and their proliferating clones.

Today, Ethernet is the main conduit of wired network communications around the world, handling data rates from 10 Mbps to 400 Gbps, with 800 Gbps and 1.6 Tbps technologies emerging. Ethernet has also become an enormous market, with revenue from Ethernet switches alone exceeding $30 billion in 2021, according to the International Data Corporation.

Metcalfe insists on calling Wi-Fi by its original name, Wireless Ethernet, for old times’ sake.

Biographical Background

Robert Melancton Metcalfe is Emeritus Professor of Electrical and Computer Engineering (ECE) after 11 years at The University of Texas at Austin. He has recently become a Research Affiliate in Computational Engineering at his alma mater, the Massachusetts Institute of Technology (MIT) Computer Science & Artificial Intelligence Laboratory (CSAIL). Metcalfe graduated from MIT in 1969 with Bachelor degrees in Electrical Engineering and Industrial Management. He earned a Master’s degree in Applied Mathematics in 1970 and a PhD in Computer Science in 1973 from Harvard University.

Metcalfe’s honors include the National Medal of Technology, IEEE Medal of Honor, Marconi Prize, Japan Computer & Communications Prize, ACM Grace Murray Hopper Award, and IEEE Alexander Graham Bell Medal. He is a Fellow of the US National Academy of Engineering, the American Academy of Arts and Sciences, and the National Inventors, Consumer Electronics, and Internet Halls of Fame.