21 November 1969: The first permanent Arpanet link

A milestone in the formation of the internet, the first permanent Arpanet link was established on this day in 1969.

The primitive network known as Arpanet was one of the key steps in the formation of the internet. Funded by the US military, it was part of research into building a communications network that could survive a nuclear war. However, the primary goal of the project was to allow computers at research institutions to access unused capacity on each other's systems.

Arpanet's big breakthrough was the use of "packet switching" technology. Previously, networks used "circuit switching", where operators manipulated circuits to create a dedicated line for sending data. Packet switching broke down data into smaller chunks that could be sent via multiple paths and then reassembled. This was faster, more efficient and, crucially, meant if part of the network was down, data could be rerouted via a different set of connections.

Drawing partly on the the work of British computer scientist Donald Davies, who first demonstrated packet switching in 1966, Arpanet sent its first message in October 1969. The first permanent Arpanet link was set up between researchers at University California Los Angeles and the Stanford Research Institute in late November. By early December two other institutions were connected.

The development of affordable computers in the 1970s drastically reduced the need for institutions to share mainframe space. But the network continued to grow after software was developed to send electronic messages, while other networks copying the technology sprang up.

By the time Arpanet was wound up in 1990, the early form of the internet had come into existence, with 300,000 systems connected worldwide.

Recommended

I wish I knew what contagion was, but I’m too embarrassed to ask
Too embarrassed to ask

I wish I knew what contagion was, but I’m too embarrassed to ask

Most of us probably know what “contagion” is in a biological sense. But it also crops up in financial markets. Here's what it means.
21 Sep 2021
Why is the UK short of CO2 and what does it mean for you?
UK Economy

Why is the UK short of CO2 and what does it mean for you?

The UK is experiencing a carbon dioxide shortage that could lead to empty shelves in supermarkets. Saloni Sardana explains what’s going on and how it …
21 Sep 2021
What to invest in to beat soaring energy prices
Investment strategy

What to invest in to beat soaring energy prices

As gas and electricity prices hit the roof, John Stepek explains how to invest to offset higher energy bills.
21 Sep 2021
Are Spacs just for suckers?
Investment strategy

Are Spacs just for suckers?

This year has seen a big boom in activity by special purpose acquisition companies (Spacs) in the US and the Spac craze is spreading to other markets…
21 Sep 2021

Most Popular

The times may be changing, but don’t change how you invest
Small cap stocks

The times may be changing, but don’t change how you invest

We are living in strange times. But the basics of investing remain the same: buy fairly-priced stocks that can provide an income. And there are few be…
13 Sep 2021
Two shipping funds to buy for steady income
Investment trusts

Two shipping funds to buy for steady income

Returns from owning ships are volatile, but these two investment trusts are trying to make the sector less risky.
7 Sep 2021
Should investors be worried about stagflation?
US Economy

Should investors be worried about stagflation?

The latest US employment data has raised the ugly spectre of “stagflation” – weak growth and high inflation. John Stepek looks at what’s going on and …
6 Sep 2021