October 29, 2009

Internet Created 40 Years Ago

Forty years ago, at 9pm October 29, 1969, engineers at the University of California in Los Angeles (UCLA) and Stanford Research Institute (SRI) prepared to transmit data between initial nodes of what was known at the time as ARPANET.

Engineer Charley Kline attempted to test the nascent network by logging on to a Scientific Data Systems computer that resided 400 miles away at SRI.

Kline began by typing the letter "L", and then asked his colleague Bill Duvall at SRI via telephone whether or not the letter had arrived.

To Kline's delight, it had.

He then typed an "O", and Duvall confirmed that too had arrived.

Kline then typed a "G", but Duvall reported that the system had crashed.  The pair restored the system by 10:30pm, after which everything worked well.

What happened next made history, changing the way millions of people throughout the world live their daily lives.

Observing the test from Washington D.C. was Dr. Larry Roberts, the MIT scientist who established the fundamental technical specifications behind ARPANET -- named after the U.S. Department of Defense's Advanced Research Projects Agency (ARPA), which commissioned the project.

The engineers who built ARPANET did so according to Roberts' design.

However, the idea of constructing ARPANET was met initially with disdain.

"They thought it was a horrible idea," Dr. Roberts told BBC News.

Bob Taylor, head of ARPA's Information Processing Techniques Office, wanted ARPANET built to eliminate the need to fund duplicate computing power at all of his research institutions.

"At the time computers were completely incompatible and moving data was a huge chore," he told BBC News.

He received some push back from institutions that sought to maintain control over their computer resources.

However, they soon realized that connecting to ARPANET would result in a vast increase in available computing power, Dr. Roberts said.

"They quickly learned that there was a tremendous gain for them."

It also allowed Taylor to meet his goal of reducing his computing costs.

At the time, the utility of a network such as ARPANET had not yet been proven, but Dr. Roberts and his colleagues had a hunch that spectacular things would happen once such a network was put in place.

"We knew that if we could connect all the data we were collecting that would change the face of research and development and business," he said.

ARPANET eventually became the Internet in the 1970s, although it was a largely superficial change.  Nevertheless, the packet switching technology behind the network was proven on that October evening four decades ago.

There were also financial incentives for developing such a packet switching network.

"The cost was enormous because we were doing it so inefficiently," said Dr. Roberts.

"We knew we needed something to share that rather than have it as a dedicated session," he told BBC News.

Dr. Roberts conducted an analysis, and found that less than 7 percent of the capacity of a telephone line used to remotely connect to a mainframe was actually used.

It would be far better to find a way to divide up that capacity among many computers, he thought.

Dr. Roberts was not alone in building a network using these principles. Indeed, computer networks had been in use before ARPANET's creation, although not many people used them.

Packet switching got its name from the late British scientist Donald Davies, who was working on building a network that used the technology at the National Physical Laboratory (NPL).

The technique made it easier, and less costly, to use telephone lines, and also accelerated the rate at which data was sent.

"If you have packets arriving in little pieces you can very quickly sort them," Roger Scantlebury, a colleague of Dr. Davies, told BBC News.

"But if you have a huge message you have to wait for that to finish before anything else can happen," he said.

Davies and his team went to work on the idea.

"When we first started we were just going to build something to show it would work, but fairly quickly Donald realized that in order for it to have any impact it needed to be a proper working system, and we actually built the network which went live at the start of 1970," he said.

"When we first put the network together at NPL, we weren't constrained by telephone wires, so we built high capacity links and everyone had 1.5 megabytes, which at the time everyone said was crazy," he told BBC News.

ARPANET grew rapidly from its first two nodes, and by December of 1969 it had doubled to four nodes. By 1972, it had 37 nodes and scientists began connecting the networks to each other.  It was then that the Internet, a network of networks, began coming to fruition.

Dr. Roberts is now driving a DARPA research project to prepare the Internet for the next 40 years.

The work is focused on improving security and fairness, so that no one entity can monopolize network capacity, and on ensuring the quality of the network can support time sensitive applications such as remote surgery.

Looking back, there is little doubt that the Internet's first step four decades ago was indeed a great leap forward.


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