Internet

History

Two researchers, Paul Baran and Donald Davies, from separate institutions, are credited with inventing the basic foundation of the Internet. Baran, a researcher at the RAND Corporation in the early 1960s, sought to create a communications network capable of surviving a nuclear attack. His premise was to build a decentralized command-and-control communications system whereby military communications could take any number of routes to their destinations. In the event that any component of the network was destroyed, the message would still arrive through the remaining parts. In 1966, Davies, a physicist at England’s National Physics Laboratory, was working on an improvement to telephone circuit switching. Both Baran and Davies independently came up with packet switching as the solution to their respective problems. Davies coined the actual term packet switching, which stuck.

Packet switching is accomplished by cutting full messages into smaller data packets. These small data packets are then sent to a series of interconnected routing stations. The routing stations accept and forward data through the most efficient route available until the data packets arrive at their final destination. If any of the routing stations go offline, as in the case of a nuclear attack, a new path is automatically chosen. Once all the data packets arrive at the final destination, the entire message is reassembled. The routing systems are asynchronous, so the individual routing stations decide the most efficient path, not the message sender. For example, depending on network conditions, the fastest way to route data packets from California to New York is through Asia to Europe and across the Atlantic. Packet switching was the framework on which the Internet was built.