Robert M. Metcalfe: IEEE 1996 Medal Of Honor Award
by R. J. Reiman, Historian
Robert M. Metcalfe has received the 1996 IEEE Medal of Honor award because of his invention of
the most widely used system for linking up computers in local-area networks (LANs). The Medal of
Honor award gave equal weight to his invention of the Ethernet technology, his promotion of
Ethernet standards, and his commercialization of Ethernet-compatible products. He has the capacity
to be praised by his former professional associates "as a brilliant individual" and "a very special guy".
His friend Howard Chaney recalls "his ability to gather together concepts that seemingly have nothing
to do with each other and to detect a hidden a hidden pattern or trend".
Metcalfe earned a degree in Electrical Engineering at MIT. While studying for a Ph D at Harvard, he
spent time for the Multiple Access Computing Project and through it met Internet founders Robert
E. Kahn and Vinton G. Cerf, and began his abiding interest in networks. An important net-related
project Metcalfe experienced was the attempt to build an interface between Bolt, Beranek, and
Newman (BBN) Interface Message Process (Imps) and Digital Equipment Corp's PDP-10 computer.
His thesis topic on packet communications at Harvard grew out of his work at MIT. To earn his Ph
D, he would have to expand on the theory.
In 1972, Metcalfe went to work for the Xerox Palo Alto Research Center {PARK} under Robert
Taylor on a mission to design the office of the future. The team at PARK succeeded gloriously by
inventing many user-friendly devices which would later earn Apple Computer, Sun Microsystems and
Microsoft such huge rewards, and achieved with distributed computing, local networking, and
interoffice mail all still applicable. Metcalfe took a leave from Xerox to join a study of a radio packet
communications network called Alohanet at the University of Hawaii, and under Norman Abramson
and Franklin Kuo. While reading a treatise of Alohanet, he began to hatch a technique for linking
computers together locally: messages would be broadcast on coaxial cable - which he eventually call
the "ether" - after the medium once postulated as the carrier of electromagnetic radiation. Each
intended destination would pick up the data packets carrying its address. If packets collided, their
non arrival would be detected by transmitters, which would back off, and after some random interval,
try again until the packets went through. Metcalfe enlisted David Boggs back at Xerox to build Alto-Ethernet interfaces, and with assistance of Tat C. Lam, made the first Ethernet transceivers which was
patented in 1975. In using the system developed, he added its theory to his thesis, and received a PH
D from Harvard.
Differences from Alohnet include no central controller, a carrier to avoid most collisions, has collision
detection, and runs at millions of bits per second rather than thousands.
From contacts on consulting agreements, Metcalfe sold his Ethernet ideas to Digital Equipment and
Intel Corp. A factor was the clarity of the Metcalfe-Boggs article on "Communications of the
Association of Computing Machinery" of July 1976. Metcalfe then founded 3Com to build Ethernet
interfaces, and the first on the market in 1980 was an interface that sold for $ 5000.00, and in 1996
is down to about $ 19.00 each. In 1982, 3Com devised the EtherLink Card which could be plugged
into IBM's first PCs.
Metcalfe and Digital's C. Gordon Bell began a struggle against giant IBM over IEEE standards
Committee 802, over local area networks. Eventually, three standards were issued, one for Ethernet,
one for IBMs "Token Ring System", and one for General Motors Token Bus system. Ethernet is now
leading the market with 50 million computers using it as a link.
Metcalfe's first marriage was dissolved in 1975 in part to his hectic life away from home. He currently has taken up writing , away from business, and his marriage to Robyn Shotwell includes two children and both a townhouse in Boston and a farm in Maine.