Connecting the World

Here’s a nifty map of the world’s undersea cables.

The era of long-distance undersea communication began with the laying of the first Atlantic telegraph cable, completed in August of 1858. Unfortunately, signal quality deteriorated rapidly and an attempt was made to improve communication by increasing the voltage at the transmitting end…a more durable cable was put in service in July of 1866.

Rapid trans-Atlantic communication made a huge difference in many spheres of life, not least in the logistics of international trade. Consider this quote from an English visitor to the US in the pre-cable year of 1852:

If, on the arrival of an European mail at one of the northern ports, the news from Europe reports that the supply of cotton or of corn is inadequate to meet the existing demand, almost before the vessel can be moored intelligence is spread by the Electric Telegraph, and the merchants and shippers of New Orleans are busied in the preparation of freights, or the corn-factors of St Louis and Chicago, in the far west, are emptying their granaries and forwarding their contents by rail or canal to the Atlantic ports.

Pre-cable, transmitting a purchase order across the Atlantic took as long (ignoring the effects of prevailing winds/currents) as the shipment of the physical goods.

Fanny Kemble wrote (circa 1882) about the psychological impact of connecting the continents electrically:

To those who know the rate of intercourse between Europe and America now, these expressions of the painful sense of distance from my country and friends, under which I suffered, must seem almost incomprehensible,—now, when to go to Europe seems to most Americans the easiest of summer trips, involving hardly more than a week’s sea voyage; when letters arrive almost every other day by some of the innumerable steamers flying incessantly to and fro, and weaving, like living shuttles, the woof and warp of human communication between the continents; and the submarine telegraph shoots daily tidings from shore to shore of that terrible Atlantic, with swift security below its storms. But when I wrote this to my friend, no words were carried with miraculous celerity under the dividing waves; letters could only be received once a month, and from thirty to thirty-seven days was the average voyage of the sailing packets which traversed the Atlantic…The distance between the two worlds, which are now so near to each other, was then immense.


Rates of information transmission on these early cables were low…Wikipedia puts the bandwidth (as we would now call it) of the 1866 cable at 8 words per minute…and message prices were correspondingly high. Improvements in telegraphy speeds were made over time, but the first trans-Atlantic undersea link capable of carrying voice traffic…the TAT-1…was not operational until 1956. It could handle only 36 simultaneous calls.

Cable’s dominant position in trans-oceanic communication was challenged by communications satellites, beginning with Telstar in 1962, but with the introduction of fiber-optic transmission (TAT-8 in 1988…40,000 simultaneous calls), cable once again took the lead over wireless in this field.

An example of a modern undersea cable system is the Emerald Atlantis, connecting the US, UK, Canada, and Iceland.  One of the major objectives of this project is to further increase the attractiveness of Iceland as a location for large data centers…it already offers the advantage of low-cost electricity from sources–geothermal and hydroelectic–that can be marketed as “green.” (Also, the chilly climate simplifies data-center cooling issues.)

“The cloud” is actually a lot less ethereal than the term would lead one to believe.

10 thoughts on “Connecting the World”

  1. That map is great. And the graphs at the bottom are extremely interesting. The growth in bandwidth is incredible and to new parts of the world. Interesting to see how quickly the proportion of US-Europe traffic has declined.

  2. There are multiple layers in conceiving a network. Virtually nobody keeps all of the layers in their heads. Many people can deal with only one at a time. The more layers you can conceive simultaneously, the closer to reality you get and the more innovative solutions to problems you can work out.

    I too liked the graph at the bottom. Corrected for population differences, I wonder if the new connectivity to Africa is ramping up faster or slower than Asian connectivity did when it started to show up on the graph years earlier.

  3. In the early 1900s, cable systems were viewed by governments…especially the British government…as strategic national assets. One of the first things the Brits did when war was declared in 1914 was to cut all the German cables.

  4. “After their telegraph cables had been cut, the German Foreign Office appealed to the U.S. for use of their cable for diplomatic messages. President Wilson agreed to this, in the belief that such cooperation would sustain continued good relations with Germany, and that more efficient German-American diplomacy could assist Wilson’s goal of a negotiated end to the war. The Germans handed in messages to the U.S. embassy in Berlin, which were relayed to the embassy in Denmark and then to the U.S. by American operators. However, the U.S. placed conditions on German usage – most notably, that all messages had to be in the clear….Obviously Zimmermann’s note could not be given to the U.S. in the clear. The Germans persuaded Ambassador James W. Gerard to accept it in coded form, and it was transmitted on 16 January 1917. At Room 40, Nigel de Grey partially deciphered the telegram by the next day.” (Wikipedia)

    The “Zimmerman telegram” directed the German ambassador to the U.S. that, in the event that the U.S. ceased to be neutral in the Great War, he should seek an alliance with Mexico, which would be supported in reconquest of Texas, New Mexico, and Arizona.

    The Brits went to great lengths to reveal the telegram to the U.S. government WITHOUT letting the U.S. know that their diplomatic communications were being intercepted and decoded.

    American anger at this telegram was one of the final straws leading to U.S. participation in WWI.

  5. There’s a cable node in downtown Miami. It’s just a building. If it were damaged a lot of the communication between Europe, the USA and Latin America would be disrupted. Connections would be rerouted but much bandwidth would be lost. Satellites wouldn’t be an adequate substitute even if the bandwidth were there, because the latency would be much higher.

    I’m sure the Chinese and others have made an effort to determine which nodes need to be damaged to knock out the bulk of our communications. I hope that we are doing similar research. The fact that the Internet routes around damage becomes moot if bandwidth is severely restricted.

  6. For those who would like some backstory on cable laying, in the early 90’s Neil Stephenson wrote an article for Wired titled “Mother Earth Mother Board”. It’s well worth a long read. (I think it runs about 80 pages or so.)

  7. In the early 1980s, I worked at an insurance brokerage company in New York that had major operations in London as well. Transatlantic phone calls were still expensive and exotic, but I needed to make them at work. They still had a room full of telex machines, and telex operators.

    At that time most of the calls were transmitted by geosynchronous satellite. Because of the distances involved, there was a noticeable lag in the calls. And if you were not being very deliberate, almost formal, it was easy to cut in on each other and make a hash of the conversation.

    How things have changed, our son is in London on business this week. He called over his iphone to his sister’s iphone via some app that is sort of like skype. We had a video chat. It was nice to see him.

    Clearly, the first connection via telegraph in the 1850s was the most significant jump in capability, but the more recent refinements have been very nice, and they make the miles of separation with loved ones easier to bear.

  8. “I’m sure the Chinese and others have made an effort to determine which nodes need to be damaged to knock out the bulk of our communications. I hope that we are doing similar research. The fact that the Internet routes around damage becomes moot if bandwidth is severely restricted.”

    This, of course, was the reason DARPA supported the “internet.” The whole packet system was to route messages by various routes to avoid interruption.

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