Paul Baran

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Paul Baran (born April 29, 1926 in Grodno , then Poland ; † March 26, 2011 in Palo Alto , USA ) was an American computer scientist of Polish descent. His eleven-part work On Distributed Communication , published in 1964, is considered to be one of the cornerstones of the development of the Internet . In it, Baran first presented the idea of transmitting information through so-called packet switching in a network with highly networked nodes.


Paul Baran was born in what was then Poland in 1926. His parents emigrated to the USA with him in 1928. Paul's father initially worked in a shoe factory and later opened a greengrocer in Philadelphia .

Baran attended the Drexel Institute of Technology (now Drexel University ). He graduated in electrical engineering in 1949 and then worked for Eckert-Mauchly Computer Corporation , where he tested radio tubes and germanium diodes for the first commercially manufactured computer. He later moved to Los Angeles and worked there at Hughes Aircraft on systems for processing and analyzing radar data . In addition, he attended courses at the University of California at Los Angeles on computers and transistors . In 1959 Baran obtained his master's degree in engineering.

Baran started working for RAND Corporation in 1959 . He worked in the Computer Science and Mathematics Department . There he later dealt with the reliability of the North American telephone network. It was the Cold War era and the US Department of Defense saw the problem of the weapon systems' ability to act in the event of a nuclear attack by the Soviet Union .

In 2001 Baran received the Bower Award and Prize for Achievement in Science .

RAND study

The RAND study dealt with the reliability of communication networks, especially the AT&T telephone network, in the event of a nuclear missile attack . At the same time in Great Britain, Donald Watts Davies , a physicist, was working on the same principle of distributed network nodes. Davies was luckier with government and telephone company support, however. Both Davies and Baran came up with the idea of ​​not only decentralizing the communication points of a network, but also dividing messages into blocks (packets to Davies). For the reasons mentioned, Donald Davies went down in the history of information technology as the founder of this partially meshed network topology and packet-switched networks .

Packet switching network design

After joining the RAND Corporation in the same year, Baran took on the task of developing a "survivable" communication system that would maintain communication between two endpoints even in the event of a nuclear attack. During the Cold War, much of the US armed forces' communications were on high frequency links. However, these connections could be put out of action for many hours in the event of a nuclear attack. Baran and Franklin R. Collbohm decided to automate the communication possibilities known from previous research via conventional AM radio networks. Through this further development, Baran and Franklin showed that a distributed relay node architecture was quite viable. The Rome Air Development Center soon expressed interest in the research results and turned them into reality. The implementation has now shown that these ideas were actually feasible.

Using the minicomputer technology that existed at the time , Baran and his team developed a simulation link to test the basic connectivity of a number of nodes, each with different degrees of connectivity. This simulation dropped randomly selected nodes, and then the percentage of nodes still connected was calculated. The result of the simulation showed that the communication network remained in place even after 50% of the node connections failed. Baran's insights from the simulation indicated that redundancy was key.


“The Internet is the work of thousands of people. Hundreds of new ideas will evolve it over the next few years. It's like a cathedral. At some point a historian comes along and asks who built the cathedral. If you are not careful and disregard the work of others, you can deceive yourself and believe that you are the builder. "

- Paul Baran : 2001



  • Janet Abbate: Inventing the Internet. The MIT Press, 2000.

Web links

Individual evidence

  1. Paul Baran's biography. In: IEEE Global History Network. March 28, 2011, accessed March 28, 2011 .