If you are in a Cold War, worried that your enemy is going to destroy your military headquarters, including your main information hub, what do you do? Design an alternative information technology in which knowledge is diffused around the whole system and accessed through many different portals.
Paul Baran, who died a fortnight ago, was one of the two inventors of packet switching, without which we wouldn’t have the internet. Martin Campbell-Kelly explains:
In 1959 he joined Rand, which had been established in 1946 to do military research for the US Air Force. By the late 1950s, it was at the centre of nuclear politics and strategy. An issue of great concern at this time was the vulnerability of US military communications to a nuclear strike from Russia. If the command-and-control network was destroyed, the ability of the US to retaliate would be threatened.
Baran invented a futuristic solution to this problem in the form of a network held together by scores of small computers. Messages would be passed (“like a hot potato”) from one computer to the next towards its destination. Even if the network was massively damaged, the message would still get through. Another innovation was to chop all messages into small blocks so that they would not be delayed by long messages clogging the network. The blocks would arrive at their destination in a random order via different routes, and the computer at the destination end would reconstitute the original messages from the individual blocks.
Baran’s digital network proposal was at the cutting edge of computer technology and would have been hugely expensive to build. Numerous technical objections were raised by senior engineers steeped in the old analogue technology. In order to answer his critics, over the next few years Baran compiled a series of 11 reports. These were never secret, because it was believed that resilient networks were needed by friend and foe alike to resolve an escalating nuclear standoff. In the end, Baran failed to gain support for his proposal and, in 1968, with two other Rand alumni, he established the non-profit Institute for the Future, where he became an authority on the emerging digital networks.
Around this time Arpa was designing the Arpanet, the prototype of the internet, and their attention was drawn to the work of both Baran and the British computer scientist Donald Davies, who had developed similar ideas at the National Physical Laboratory in Teddington, Middlesex. Davies (who was unaware of Baran’s work) called his system “packet switching”, and that name stuck, although the underlying concepts were the same in both proposals. Most importantly, both Baran and Davies had conducted and published detailed studies which established packet switching as a viable technology rather than just a bright idea. This enabled Arpa to commit to the system, and it remains the underlying technology of the internet.
It makes one reflect on how knowledge is stored and shared in other systems – in academia, in politics, in family life, in religions, etc.
Baran seems to have been very humble about his achievements, and keen to acknowledge the work of many others in building the internet. Katie Hafner writes:
In recent years, the origins of the Internet have been subject to claims and counterclaims of precedence, and Mr. Baran was an outspoken proponent of distributing credit widely.
“The Internet is really the work of a thousand people,” he said in an interview in 2001.
“The process of technological developments is like building a cathedral,” he said in an interview in 1990. “Over the course of several hundred years, new people come along and each lays down a block on top of the old foundations, each saying, ‘I built a cathedral.’
“Next month another block is placed atop the previous one. Then comes along an historian who asks, ‘Well, who built the cathedral?’ Peter added some stones here, and Paul added a few more. If you are not careful you can con yourself into believing that you did the most important part. But the reality is that each contribution has to follow onto previous work. Everything is tied to everything else.”
