FEATURE
SUBMARINE CABLES: An Amazing Oldster With New Life
W
hat is the most important and omnipresent component of our international economy? One might get many and varied answers to that question depending on the backgrounds and interests of the audience. But this author suggests that the only answer that makes sense is submarine cables. Today these cables carry 94% (+- 5%) of all international network traffic. Without this network of under water cables international banking, worldwide commerce, international transportation systems, a great deal of defense infrastructure, and the global availability of news that we are so accustomed to would cease to exist. This article will review the current status of international submarine cables and provide an indication of why this is the hottest of telecom markets. Before we look at typical current submarine cable configurations and growth forecasts, it will be constructive to review their amazing history.
HISTORY
It is remarkable that a major and indispensable component of the network we call the Internet goes back over 150 years - actually before the Civil War! These old-timers are international submarine cables. The first true international and first trans-Atlantic cable was installed between Newfoundland and Ireland in 1858 (used of course, for telegraphy use as the telephone was decades away.) The list of early advocates and developers of the undersea cable technology
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SUBMARINE TELECOMS MAGAZINE
BY CLIFFORD R. HOLLIDAY reads like a listing of the most important pioneers in telecommunications, including Morse, Faraday, Wheatstone, Cyrus West Field and Oliver Heaviside. On August 16, 1858, Queen Victoria and President James Buchanan exchanged telegrams on the new cable. It took a ‘mere’ 17 hours and 40 minutes to transmit, the brief correspondence (fewer than 100 words in total.) But even at that tortoise speed, this represented the fastest message ever sent between Washington and London to that time. This first cable was actually placed before the basic engineering was understood for transmission lines, which grew out of transmission line work done by Maxwell, Kelvin and Heaviside between the 1850s through the 1880s. The lack of understanding of this basic engineering led to the destruction of this first trans-Atlantic cable a few weeks after it was placed in service. One of the owners tried to increase its speed by upping the voltage. The higher voltage resulted in the cable shorting out to the water and thus destroyed it. But while it would take another 6 years for it to be replaced, this pioneering installation marked the first step in a communications revolution that would lead, ultimately, to the creation of the international Internet. This first trans-Atlantic cable actually never worked very well, and eventually destroyed itself. Michael Faraday showed that the effect was caused by capacitance between the wire and the earth (or water) surrounding it. Faraday had noticed that when a wire