Donald Watts Davies
(June 7, 1924—May 28, 2000)
(Photo credit: © Crown copyright 1974.
Reproduced with the permission of the Controller of HMSO and the Queen's Printer for Scotland)
Donald Davies’s crucial breakthrough of packet switching, which
enables the efficient exchange of information between computers,
makes modern computer communications both functional and robust.
Born in Treorchy, Wales, Davies studied at the Imperial College
in London, earning his B.S. in physics and mathematics.
Following graduation, he worked at the National Physical
Laboratory in England pursuing ways to broaden the use of
computers. In 1965, Davies designed and implemented the first
operational packet switching network. Packet switching, a term
coined by Davies, was based on the concept of sending
information in small digital “packets” through a distributed
system, with each packet able to take a different path from
sender to receiver, rather than over a conventional dedicated
After proving its feasibility in the United Kingdom, Davies
worked with the Advanced Research Projects Agency in the U.S. to
create a larger, universal network. Davies’ concept of breaking
up packets of information was quickly implemented in ARPANET,
the precursor to the Internet.
Digital packet switching enabled the construction of data
networks with greater flexibility and throughput while laying
the technical foundation for the eventual development of TCP/IP,
the Internet Protocol.
Leroy E. Hood
John Joseph Lynott