Biography of Donald Davies
Continued...He showed managerial skills as well as technical ability and in 1966 was appointed head of what was soon to become NPL's Division of Computer Science. An important new project was the development of an idea he had originated in 1965:- the concept of Packet Switching.
In 1979 realising the threat of malicious interference on computer networks, he started a group to work on Data Security, concentrating on the new method of public keycryptosystems. The group built a strong consultancy role round his expertise; all the major UK clearing banks, for instance, used its services. He retired from NPL in June 1984 and continued his work as data secirty consultant.
His versatility and fascination with intellectual challenges is evident in his private interests as well as in his official work. These included the design and construction of noughts-and-crosses machines, which, in the days before home computers, were considerable attractions at the annual NPL children's parties; cryptographic machines, particularly the German machines of the Second World War; and all puzzles and games capable of mathematical analysis.
His last project showed that his technical skills remained undiminished: he developed a simulator of the Pilot ACE for a modern personal computer, demonstrated in May 2000 at a conference celebrating the machine's 50th anniversary, though illness sadly prevented him from attending.
Donald Davies married Diane Burton in 1955 and had a daughter and two sons. He died on 28th May 2000 at the age of 75.



