Evolution of the internet: Celebrating 50 years since Arpanet

50 years after the birth of the internet's precursor, Arpanet, there are more internet-connected devices than people in the world, and traffic is measured in exabytes.

NW_internet 50th anniversary2
Blueberries / Getty Images

Arpanet carried its first message on October 29, 1969, laying the foundation for today’s networked world. Fifty years later, more than 4 billion people have internet access, and the number of devices connected to IP networks is more than double the global population. Here’s a look at some key milestones in the history of the internet and  projections for its future growth.

Arpanet, precursor to the internet

The name Arpanet came from the U.S. military arm that funded it, the Advanced Research Projects Agency. When Arpanet was created, it connected five sites: UCLA, Stanford, UC Santa Barbara, the University of Utah and BBN Technologies.

The first Arpanet node was set up at UCLA on Aug. 30, 1969. The second node, at the Stanford Research Institute, was set up on Oct. 1. The first data message sent between the two networked computers occurred on Oct. 29, when UCLA computer science professor Leonard Kleinrock sent a message from his school's host computer to another computer at Stanford. Kleinrock intended to write "login" to start up a remote time-sharing system, but the system crashed after only two letters, "l" and "o", were transmitted.

In 1983, the U.S. Defense Department spun-off MILNET, which was the part of Arpanet that carried unclassified military communications. (MILNET was later renamed the Defense Data Network and finally NIPRNET, for Non-classified IP Router Network.) Arpanet was renamed the internet in 1984, when it linked 1,000 hosts at university and corporate labs.

To continue reading this article register now

SD-WAN buyers guide: Key questions to ask vendors (and yourself)