On November 22, 1977, as it motored down the street somewhere south of San Francisco, a souped-up delivery van sent some information to a computer lab at the University of Southern California, 400 miles away. No one can quite remember what the information was, but that really doesn't matter. What matters is the way it travelled.
It didn’t travel as the crow flies. It traveled from San Francisco to Boston, before a trip to Norway and Britain. And from Britain, it bounced back to Southern California by way of a tiny town in West Virginia.
And it didn’t travel over one data network. Thanks to a certain protocol called TCP, it traveled over three: a wireless packet radio network covering a few California hilltops, a satellite hookup bridging the Atlantic, and the Arpanet, a wired network that would go on to much bigger things.
For some, this dipsy-doodle data transmission marks the world’s first internet connection. But you can disagree if you like.
The thirtieth anniversary of this little-known event was celebrated last week at the Computer History Museum in Mountain View, California, not far from where the souped-up delivery van did its transmitting. TCP founding fathers Vint Cert and Bob Kahn were on hand, along with 16 others who helped send those packets across the world and back again.
“The point is that we did this over three separate networks,” Cerf told us. “It was true inter-networking.”
‘The bread truck’
The delivery van — which looks an awful lot like an old-school bread truck — belonged to SRI International, the research center most famous for cooking up hypertext and the computer mouse. Since about 1975, the van had operated as a “mobile node” on a packet radio network that stretched across Silicon Valley and up to San Francisco.
SRI had built this wireless network with more than a little help from the University of California Los Angeles (UCLA) and a trio of private contractors: Bolt Beranek and Newman of Boston, Collins Radio of Dallas, Texas, and Network Analysis near New York City. But it was funded by DARPA (Defense Advanced Research Projects Agency), the defense department operation where Cerf and Kahn spent time developing the Transmission Control Protocol. You know, TCP – the protocol that now drives the internet.
DARPA, of course, had already bootstrapped the Arpanet, a packet switched network spanning various government agencies and academic institutions. The Arpanet, as you all know, eventually morphed into the worldwide extravaganza we use today.
But as a defense department operation, DARPA also saw the need for wireless transmission. “When you’re in a militarized environment and you’re mobile, you can’t have wires,” Cerf said. “Tanks with wires don’t work very well.”
According to a Computer History Museum hype-machine, this 100 to 400 Kbps packet radio network “foreshadowed WiFi.” And that sounds about right. It was only slightly more difficult to deal with.
“I was the only guy who could sit in a room where a demo was going on and tell that the packet radio network was actually working,” said Cerf. “I have hearing aids, and they would pick up the signal. It sounded like crinkling paper. So when the crinkling paper noise stopped, I would kick the technician under the table and he would re-power the equipment.”