How and when did the early Internet reach the UK? In fact, the story of how the prototypical ARPANet got here is a mixture of cold-war intrigue, bungling bureaucracy, and British pragmatism. Join Peter H. Salus on this fascinating journey...
The Internet today supports over a billion connected machines all over the world: desktops, tablets, laptops, phones, connected refrigerators, and what-have-you. But in December 1969, there were just four nodes on the ARPANet—the pioneering forerunner of today’s Internet. All were in the western US (three in California, one in Utah).
By June 1970 there were nine sites, adding three in Cambridge, Massachusetts. The sites were linked by IMPs—Interface Message Processors, effectively the first routers.
But by 1973, a US Department of Defense map shows a place called London. Let me tell you how the Net reached across the Atlantic.
The ARPANet in 1973, courtesy Alex McKenzie of BBN
The tale takes us back a decade. The US government wanted to monitor atomic tests in the USSR. It set up an array of detectors to differentiate between seismic noise arising from natural and man-made sources. The first of these arrays was the Large Aperture Seismic Array (LASA) in Montana, in 1965. But developing seismic array technology in the US alone had the downside of poor teleseismic discrimination: you couldn’t tell whether a far-away rumbling was an earthquake or a test. LASA was too close to the only source of nuclear explosions for calibration: the Nevada Test Site.
But the experience gained from LASA was used in the installation of a second large array, the Norwegian Seismic Array (NORSAR), placed at a teleseismic distance (greater than 1,000 km) from both US weapon tests and those of the USSR in Kazakhstan. The Norway array was approved in January 1967 and became operational in February 1971. LASA and NORSAR recorded signals from nuclear events in the USSR, which allowed corroboration of data.
Data from the arrays were analysed at the Seismic Array Analysis Center (SAAC) in Alexandria, Virginia, whose Terminal Interface Processor (TIP)—essentially a standalone IMP that allowed the terminal’s direct connection to the ARPANET—was installed by August 1972. The installation of a TIP at NORSAR occurred at the same time.
It fell to Professor Peter Kirstein's research group at University College London (UCL) to link to the ARPANET, which for the next 15 years gave Britain a view of what was happening in the US. To anyone outside the UK, the next stages were hilarious.
To connect the UK to the ARPANET required the use of a TIP furnished by ARPA. On arrival at Heathrow, the TIP was impounded by Customs and Excise for duty to be paid plus an additional £5,000 for Value Added Tax, neither of which had been anticipated. The UK Science Research Council (SRC) held that this connection (UK to US) did not present a particularly fruitful opportunity and declined to provide the funding needed. Kirstein raised the funds, anyway.
The next problem arose when the Scandinavian Tanum satellite ground station came on line, which allowed the retrieval of NORSAR data at 50 kb/s for the first time. This upgrade of bandwidth obviated further need for the 9.6 kb/s cable line that passed through London enroute to Norway. A new London–Norway link was needed to connect to the new Norway–Washington link, but the tariff proposed by the carriers acting under the umbrella International Telegraph and Telephone Consultative Commission (CCITT) was beyond any possible budget provision.
The French wanted the tariff to be priced at the number of multiples of 2.4 kb/s voice circuits to achieve the ARPANET speed of 50 kb/s. The British Post Office—this was before the days of British Telecom—offered to provide the link free for a year. Later, an appeal to the Post Office to provide a 50 kb/s link from their satellite station at Goonhilly Downs was approved. They provided the use of the satellite link on a research basis, and thus circumvented the French roadblock.
Less than a decade later, USENET came into existence in the US, and thanks to Armando Stettner, then of DEC, the Mathematics Centre in Amsterdam was connected. But how to get USENET’s netnews service to the UK? That tale involves Peter Collinson, then at the University of Kent in Canterbury, and a group of what we'd now consider hackers in the Netherlands and the UK. I'll save it for another time.
Here’s a tip of the hat to Peter Kirstein and UCL, for bringing us the first connection to the prototypical Internet outside the US.
My sources include several articles by Prof. Kirstein, such as Early Experiences with the ARPANET and INTERNET in the UK.