
- Donald Davies
Donald Davies and his colleagues at the
UK National
Physical Laboratory independently discovered
the idea of packet switching,
and later developed a smaller scale packet-switched version of
the ARPANET.
In 1965, while Donald Davies was Superintendent of the National
Physical Lab (NPL) in Britain, he proposed development of a country
wide packet communications network. He gave a talk on the proposal
in 1966, and afterwards a person from the Ministry of Defence told
him about Paul Baran's work for
RAND being done independently. In one of those coincidences so
pervasive in the history of science, Davies had independently decided
upon some of the same parameters for his network design as Baran,
such as a packet size of 1024 bits.
At the 1967 ACM Symposium
on Operating System Principles, Lawrence
Roberts met Davies and Roger Scantlebury from the NPL,
who had published a paper at the conference titled A Digital
Communications Network For Computers. As Roberts continued
his planning at ARPA to build a wide area communications network,
the terms "packet" and "packet switching" were
taken from Davies work.
In 1970, Davies helped build a packet switched network called
the Mark I to serve the NPL. The Mark I had only a few nodes within
the NPL, and operated at a speed of 768 kbps. It was replaced with
an improved network called the Mark II in 1973, and remained in
operation until 1986, but it never had the funding to develop on
the scale of the ARPANET.
Resources. The following paper provides more information
on the NPL: