Donald Davies facts for kids

Quick facts for kids Donald Watts Davies CBE FRS
Born	(1924-06-07)7 June 1924 Treorchy, Glamorgan, Wales
Died	28 May 2000(2000-05-28) (aged 75) Esher, Surrey, England
Alma mater	Imperial College
Known for	Packet switching
Awards	CBE, FRS Distinguished Fellow, BCS
Scientific career
Fields	Computer science
Institutions	National Physical Laboratory

Donald Watts Davies (born June 7, 1924 – died May 28, 2000) was a brilliant Welsh computer scientist. He worked at the National Physical Laboratory (NPL) in the UK.

In 1965, Donald Davies came up with the amazing idea of packet switching. This is a super important way that computers send information to each other today. It's how the Internet works! He designed a special computer network called the NPL network to show how his idea worked. Many early computer networks used his design. The team behind the ARPANET, which was an early version of the Internet, said that Davies's ideas were very important to their work.

Davies developed his ideas on his own. Another scientist in the United States, Paul Baran, had a similar idea around the same time. Both of their ideas helped shape the Internet we use today.

Early Life and Education

Donald Davies was born in Treorchy, a town in Wales. His father passed away when Donald was very young. His mother then moved with Donald and his twin sister to Portsmouth, England, where he went to school.

He studied physics at Imperial College London and earned a degree in 1943. During World War II, he helped with a secret project called Tube Alloys, which was about nuclear weapons. After the war, he went back to Imperial College and earned another degree, this time in mathematics, in 1947. He was even awarded a special prize for being the best mathematician that year.

Working with Computers

At the National Physical Laboratory

In 1947, Davies started working at the NPL. This was where Alan Turing, a famous computer scientist, was designing an early computer called the Automatic Computing Engine (ACE). Davies even found some small errors in Turing's famous paper about computers!

The ACE project was very ambitious. Davies took over the project and focused on building a simpler version called the Pilot ACE. This computer started working in 1950. A company later made a commercial version of it called DEUCE, which became very popular in the 1950s.

Davies also worked on other projects, like how to simulate traffic and how to translate languages using computers.

The Big Idea: Packet Switching

In 1965, Davies came up with his most famous idea: packet switching. Imagine you want to send a long message, like a letter. Instead of sending the whole letter at once, packet switching breaks the message into small pieces, like tiny postcards. Each "postcard" is called a packet. These packets then travel across the network, sometimes even taking different paths, and are put back together at the other end.

Davies chose the word "packets" carefully after talking to a language expert. He wanted a word that would be easy to translate into other languages. He realized that computer information is often sent in short bursts, not like a constant phone call. This was a key insight for his design.

In 1966, Davies returned to NPL and became the head of their computing work. He visited the Massachusetts Institute of Technology and saw that connecting many computer users was very expensive. This made him think about better ways to send data. He was the first to describe an "Interface computer" in 1966, which we now call a router. His team also used the word "protocol" for the first time in computer communication in 1967. A protocol is like a set of rules for how computers talk to each other.

His work on packet switching got the attention of the people building the ARPANET in the US. Larry Roberts used Davies's ideas for the ARPANET, which was a very important step towards creating the Internet.

Davies first shared his ideas about packet switching at a conference in Scotland in 1968. At NPL, he led the creation of the Mark I NPL network, a local packet-switched network. It was later updated to the Mark II in 1973 and was used until 1986. This network influenced other computer research in Europe.

At the same time, Paul Baran in the US was also working on a similar idea. When Baran learned about Davies's work, he agreed that they had both discovered the concept independently. He even sent Davies an email saying, "You and I share a common view of what packet switching is all about, since you and I independently came up with the same ingredients."

Connecting Networks (Internetworking)

Davies and his team also researched how different computer networks could talk to each other. This is called internetworking. They helped create rules for how networks should communicate.

In 1973, Davies and his colleague Derek Barber published a book called "Communication networks for computers." They talked about the challenges of making different networks work together. For a long time, experts debated which type of network rules would be best. Davies's team at NPL experimented with connecting their network to others, showing that having common rules made connections more reliable.

Computer Security Work

In 1979, Davies decided to focus on research again. He became very interested in computer network security. He helped design the Message Authenticator Algorithm (MAA) in 1983. This was one of the first widely accepted ways to make sure that a message had not been changed during its journey. It became an international standard in 1987.

Davies retired from NPL in 1984. After retiring, he became a top expert on data security for banks and wrote a book about it.

Awards and Recognition

Donald Davies received many honors for his important work:

• He was named a Distinguished Fellow of the British Computer Society (BCS) in 1975.
• He was made a CBE in 1983.
• He became a Fellow of the Royal Society in 1987.
• In 2000, he shared the first-ever IEEE Internet Award.
• In 2007, he was added to the National Inventors Hall of Fame.
• In 2012, he was inducted into the Internet Hall of Fame by the Internet Society.

A special museum gallery about packet switching and the Internet was opened at The National Museum of Computing in 2009, sponsored by NPL. A blue plaque honoring Davies was placed in his hometown of Treorchy in 2013.

See also

• History of the Internet
• Internet in the United Kingdom § History
• Internet pioneers