Arpanet developer Larry Roberts dies aged 81

Larry Roberts, one of the main developers of internet precursor Arpanet, has died at the age of 81. Roberts developed Arpanet and encouraged others to build applications for it, such as email.

Roberts in 2017

Roberts died on Boxing Day of a heart attack at his home in Silicon Valley, Redwood City, his son told The New York Times. His colleague Vint Cerf confirms that. Roberts worked on the architecture of Arpanet and made Arpanet use the newly invented packet switching, in which data to be sent over a network is divided into packets that are sent over the network independently of each other. Today’s internet still uses that technology. Arpanet, which Roberts largely designed and implemented, is considered the earliest precursor to the Internet.

Before that, Roberts had been experimenting with 3D graphics. For example, together with a classmate, he had built an input mechanism to manipulate 3D objects on a screen, the Lincoln Wand. It worked with ultrasonic signals and looked like a magic wand.

After working at Arpanet, he founded a company to make packet switching a huge success and sold it seven years later. After that he founded many more companies, but he says he did not become rich from his work. He was awarded the 2001 Draper Prize for his work on Arpanet, together with Cerf, among others.