Submarine cabling network always seems to be a myth. We are surprised by the achievement when we see today’s global submarine cables map but we can not imagine that how cables can be laid in the coldest depths of the ocean and how do they work. Most people think the internet is beamed around the planet by satellites. Actually, most of the world’s people, businesses and institutions are connected by submarine cables. These submarine cable systems carry the vast majority of our international communications and data. Meanwhile, they form the backbone for the data centers powering the world wide web. Here are some interesting things you might probably not know about submarine cables. When you know these facts, submarine cables may no longer be a myth.
Many people notice the submarine cables thanks to the activity of Google Fiber in recent years. In fact, the history of submarine cables originated in 1850s. The first submarine communications cables, laid in the 1850s, carried telegraphy traffic. And in 1866, the transatlantic submarine cable was completed, and submarine cable networks in the world were expanded gradually. However, the first transatlantic fiber optic cable (TAT-8) was laid in 1988. Over the years fiber optic cables were laid across the world, connecting economies and societies increasingly dependent on telecommunications.
Laying submarine cables is a remarkably slow, complex, hazardous and expensive business. Before laying cables, many surveys shoud be done to ensure the installation work smoothly. For instance, routes need to be surveyed, technology developed, the cable needs to be laid without being lost, broken or damaged. The seabed is as hilly, rocky and varied as any terrain on land—so undersea cable expeditions have always started with surveys to find relatively flat and unbroken routes. It is a very complex work. In addition, it need great deal of human labor that real men and women toil long and tedious hours to make this possible. There days, with the developing technology, new cables tend to be buried using robot submarine ploughs that crawl along the seabed. But such big scale projects are still expensive and lengthy.
You may think that your Internet is carried by the satellites. You may know there are well over a thousand satellites in orbit and praise their performance. However, the truth is that over 99% of international communications are delivered by submarine cables. Even in the age of satellites, the development of submarine cables are faster than the satellites. Satellites have a two-fold problem: latency and bit loss. Sending and receiving signals to and from space takes time. Meanwhile, researchers have developed optical fibers that can transmit information at 99.7% the speed of light. Submarine cables are faster, process more data, more reliable and last longer than satellites.
As we know, cables laying underground often face a variety of damage. For example, construction companies and excavators seem like the natural enemy of buried cables. While the ocean is free of construction equipment that might otherwise combine to form Devastator, there are many ongoing aquatic threats to the submarine cables. Sharks aside, the cable is ever at risk of being disrupted by boat anchors, trawling by fishing vessels, and natural disasters.
Sharks like to eat our submarine cables. This is because the cables disturb their normal life, but not the cables are delicious. The most recognized reasons now for sharks biting fiber cable are that fiber will emit a weak electrical field that will be picked up by the sharks’ sensory system. Sharks are chewing on the submarine cables, and sometimes damage it. In response, companies such as Google are shielding their cables in shark-proof wire wrappers.
You must be wrong if you think sharks are the only living things to damage the submarine cables. Many people think that it is hard to cut through a submarine communications cable, because of the thousands of very lethal volts running through each of them. This is why people believe that “living” enemy of submarine cables is only shark. However, this is not the case. In the last three years, there are man-made damage cases happened which make this impossible thing become possible. For example, in Egypt in 2013, north of Alexandria, men in wetsuits were apprehended having intentionally cut through the South-East-Asia-Middle-East-West-Europe 4 cable, which runs 12,500 miles and connects three continents. Internet speeds in Egypt were crippled by 60% until the line could be repaired.
During the height of the Cold War, the USSR often transmitted weakly encoded messages between two of its major naval bases. Strong encryption was a bother—and also overkill—thought Soviet officers, as the bases were directly linked by an undersea cable located in sensor-laden Soviet territorial waters. No way would the Americans risk World War III by trying to somehow access and tap that cable. They didn’t count on the U.S.S. Halibut, a specially fitted submarine capable of slipping by Soviet defenses. The American submarine found the cable and installed a giant wiretap, returning monthly to gather the transmissions it had recorded. This operation, called IVY BELLS, was later compromised by a former NSA analyst named Ronald Pelton, who sold information on the mission to the Soviets. Today, tapping submarine communications cables is standard operating procedure for spy agencies. Spies love submarine cables. Yes, it’s really a threat to country’s safety. Thus, governments must to do something that can avoid said spies. With respect to electronic espionage, one big advantage held by the United States is the key role its scientists, engineers, and corporations played in inventing and building large parts of the global telecommunications infrastructure. Major lines of data tend to cross into American borders and territorial water, making wiretapping a breeze, relatively speaking. When documents stolen by former NSA analyst Edward Snowden came to light, many countries were outraged to learn the extent to which American spy agencies were intercepting foreign data. As a result, some countries are reconsidering the infrastructure of the Internet itself. Brazil, for example, has launched a project to build a submarine communications cable to Portugal that not only bypasses the United States entirely, but also specifically excludes U.S. companies from involvement.
We can imagine that in the coldest depths of the ocean, cable repair is a very difficult work. This is a pain just like that you can’t quite reach behind your desk when you decide to replace an Ethernet cable. Because we can’t reach the bottom of the ocean. However, people always have a way to solve this problem. When a submarine cable is damaged, special repair ships are dispatched. If the cable is located in shallow waters, robots are deployed to grab the cable and haul it to the surface. If the cable is in deep waters (6,500 feet or greater), the ships lower specially designed grapnels that grab onto the cable and hoist it up for mending. To make things easier, grapnels sometimes cut the damaged cable in two, and repair ships raise each end separately for patching above the water.
To ensure that submarine cables operate, without failure, they are designed for a minimum lifespan of 25 years. As of 2014, there are 285 communications cables at the bottom of the ocean, and 22 of them are not yet in use. These un-used cables are called “dark cables”. Submarine cables have a life expectancy of 25 years, during which time they are considered economically viable from a capacity standpoint. Some people may ask “Is a 25-years design life long enough, or do cable owners now hope to extend the “retirement” of their cable beyond this point? Will the cables actually last that long? …” Actually, some large submarine cable companies have already publicly announced that they now expect their submerged equipment to be practically and economically viable for at least 25 years (and perhaps 30 years) thanks to SLTE technology upgrades.
More than 550,000 miles of flexible submarine cables about the size of garden watering hoses carry all the world’s emails, searches, and tweets. Together, they shoot the equivalent of several hundred Libraries of Congress worth of information back and forth every day.