Jeremy Keith:
You probably heard that the Internet was created to withstand a nuclear attack, right? A network that would be resilient to withstanding a nuclear attack, and that’s actually not quite true. What is true is that Paul Baran, who was at the Rand Corporation, was looking into what is the most resilient shape of a network. And amongst his findings, one of the things he discovered was that by splitting up your information into discrete packages, it made for a more resilient network, and this is where this idea of packet switching comes from that you take the entire message, chop it up into little packets, and then you ship those packets around the network by whatever route happens to be best and then reassemble them at the other end.
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Now what’s interesting is that, Bob Kahn and Vince Cerf, back then they weren’t concerned about making the network resilient to nuclear attack. They were young, idealistic men, and what they were concerned about was making a network that was resilient to any kind of top down control, so that was kind of baked into the design of these protocols that the network would have no centre. The network has no single decision point. You don’t have to ask to add a node to the network. You can just do it.