Paul Baran. (© 2011 IEEE)

Paul Baran, who dreamed up what became the internet’s fundamental architecture, an idea so out-of-this-world 50 years ago that AT&T wouldn’t deal with him, has died. He was 84.

The New York Times reports that Baran died on Saturday from complications of lung cancer.

Baran was working at the famed RAND corporation on a “survivable”communications system in the early 1960s when he thought up one of its core concepts: breaking up a single message into smaller pieces, having them travel different, unpredictable paths to their destination, and only then putting them back...