Undersea Fiber-Optic Cables Connecting World’s Oceans With the Internet

Ever wonder where the bandwidth comes from that makes Gmail and YouTube videos run so smoothly? Google uses its private “B4 Network” which is a undersea network of fiber optic cables. In fact, 99% of the world’s international communications occur beneath the ocean’s waves.

As far back as the 1860’s, the British laid telegraph cables on the ocean floor into the Mediterranean Sea and the Indian Ocean as a convenient way to communicate with governors throughout its empire and to conduct diplomatic and military communications.

In the early days of undersea cable unreliable performance was rife and cables short-circuited due to voltage overloads, were cut or sabotaged, got entangled with whales or were severed by large undersea mudslides.

But the advantages to be gained from operational cables were so great that 30 cables were laid by the turn-of-the-century, two thirds operated by the British. During World War I British and German forces competed to destroy communication lines by cutting underwater cables with surface ships and submarines. During World War II, opposing sides frequently cut cables and redirected the flow of information to code breakers.

During the 20th century cables were cut as they were dragged out of position by fishing nets. And in 2007 a seven mile (11km) cable with 100 tons of copper was cut from a section of the T-V-H cable connecting Thailand, Vietnam and Hong Kong; pirates were arrested attempting to sell the metal as scrap.

Over time the number of underwater communication cables has multiplied exponentially and rest on the floors of all the world’s oceans, except for Antarctica, which even today presents technological challenges that have yet to be overcome. Fiber-optic cable needs to withstand temperatures of -80°C and resist strain from ice flows despite the fact that it’s less malleable than copper.

Modern Undersea Cables

Modern undersea communications cables use fiber-optic technology to carry data, phone, Internet, as well as private data traffic. Undersea cables are now fit with GPS devices so they can be located quickly when repairs are necessary. Methods of laying deep-sea cables have been revolutionized so that the cost is now just $1000 per mile. Thinner cables are used for shallow ocean depths and thicker cables for deep ocean beds. Some cable is laid as deep as 20,000 feet and needs to withstand from 12,000-22,000 pounds per square inch of pressure.

A New Type Of Fishing

With the huge number of undersea cables, scientists are beginning to study the oceans by connecting the seafloor to the Internet. A project called NEPTUNE Canada is connecting hundreds of oceanographic instruments to a 500 mile (800km) fiber-optic cable that circles the northern Juan de Puca tectonic plate.

With projects such as this coming online all the time, a continuous data stream will allow scientists to study the ocean and address issues such as earthquakes, acidity and climate change.

Sea Cables of the World

Tags: communication, undersea cables

This entry was posted on June 27th, 2014 and is filed under Electrical. Both comments and pings are currently closed.