- Person
- Paul Baran
- Lived
- 1926–2011
- Field
- Computer networking
- From
- Polish-born American
The story
Paul Baran was born Pesach Baran in 1926 in Grodno, then in Poland, to a Lithuanian Jewish family that emigrated to the United States when he was two. He grew up in Philadelphia, where his father ran a grocery store and Paul delivered orders in a small red wagon. After studying electrical engineering at Drexel and working on early computers, he joined the RAND Corporation in 1959.
The Cold War posed a frightening problem. Military planners feared that a nuclear attack would destroy the few central switching centres on which telephone and command networks depended, leaving the country unable to communicate even if most lines survived. Baran’s answer was to do away with the centre. He proposed a distributed network of many simple nodes, each linked to several neighbours. His team’s computer simulations, which randomly destroyed nodes, showed that with at least three links per node such a network stayed largely connected even after heavy damage. Redundancy was the key.
He also proposed cutting every message into small standard pieces, which he called message blocks. Each block would travel separately by whatever route was open and be reassembled at its destination; if a node failed, the blocks went around it. He published the full design in RAND’s series On Distributed Communications in 1964. AT&T engineers scoffed, and the company refused to build it. In Britain, Donald Davies independently developed the same idea and named the pieces packets, and historians credit both men with inventing packet switching.
When the Pentagon’s research agency built the ARPANET in 1969, its planners drew on Baran’s RAND volumes among other sources. The ARPANET grew into the internet, and packet switching still lies at the heart of how it works. Baran always insisted that the internet was the work of a thousand people, comparing invention to building a cathedral stone by stone. He went on to found companies whose technologies helped bring wireless and cable internet access to homes.
Why it matters
Every email, video call and web page today travels as packets across a network that can route around failures, the design Baran helped invent.
About Paul Baran
Grocer’s son from Philadelphia who worked out how to send data in small blocks across a web of routes. Packet switching, his idea and Donald Davies’s, still carries the internet.
Sources
- Paul Baran, Internet Pioneer, Dies at 84 The New York Times
- Paul Baran and the Origins of the Internet RAND Corporation
- Paul Baran Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.