Microsoft and Facebook to build new sub-sea cable: 6 interesting facts about undersea Internet cables

A map from 2006, showing how much capacity the world has in terms of undersea cables that carry Internet traffic and voice calls. PHOTO: PRIMETRICA

On Thursday (May 26), Microsoft and Facebook announced that they will be building a high-speed Internet sub-sea cable that will connect the United States and southern Europe across the Atlantic, in order to meet growing demands for faster and more reliable services.

Microsoft's cloud services such as Skype, Xbox Live, Office 365, search engine Bing and its cloud computing platform Azure will benefit from the construction of this cable.

This 6,600km cable network, also known as the Marea cable, has an estimated capacity of 160 terabytes of data per second and is expected to be constructed in August and completed by October 2017.

Marea is Spanish for "tide" and this cable that stretches from Northern Virginia to Bilbao, Spain, will be operated by Telxius, a telecommunications infrastructure company owned by Spanish company, Telefonica.

When completed, the Marea cable will be one of many connecting the world.

Here are six interesting facts about the Internet's undersea backbone:

1. Singapore is known to be one of the world's top submarine cable hubs

Singapore is an air hub, a sea hub, and a data hub.

Even before the 1900s, Singapore was a landing point for submarine telegraph cables carrying messages between Britain and Asia.

Today, many modern submarine cable systems land in Singapore, connecting it to countries in every continent but Antarctica.

The country is a node for as many as 16 submarine cables for international telecommunications and networks, as of October 2015.

These amount to a data transmission capacity of more than 114 terabytes per second.

2. The life expectancy of an undersea cable is approximately 25 years

TeleGeography's submarine cable map, updated for 2016, listed 293 active and 28 planned cable systems. Planned cable systems refer to those that are currently being constructed or are expected to be fully-funded by the end of this year.

Once these cables are active, they are expected to have a life expectancy of 25 years before they are required to undergo replacement and repairs.

Special repair ships are dispatched to perform these repairs.

If the damaged part of the cable is less than 6,500 feet down, a robot is used to bring the cable to the surface. However, if the depth of the cable is too deep, a grapnel is used instead to haul the cable up for repair.

3. Installing cables is an expensive and arduous process

If you have trouble installing a television or a computer, just imagine how challenging it would be to install an entire network of cables under the sea.

The process of laying undersea cables is often a tedious one which requires long hours and ample manpower.

Huge modified ships lay these cables along the ocean floor and they have to ensure that these cables are buried properly, while trying to avoid coral reefs and other forms of ocean life on the sea bed.

Cable ships can lay around 100-200km of cable per day.

4. Their widths vary according to where they are placed in the ocean

Undersea cables are more vulnerable to threats - such as sharks and ships - in shallow waters and hence tend to be thicker in width, approximately the width of a soda can.

However, at a deeper level, they are usually thinner, around 17mmwide.

These cables are often covered in a protective layer and have a core comprising optic fibres and wires.

They can be found even at a depth of 8,000m, which is about the height of Mount Everest.

5. Cables are often damaged by external sources and are susceptible to attacks by spies and saboteurs

Sharks too, enjoy biting these undersea cables and the reasons behind this strange phenomenon is unclear.

There had already been cases of sharks exhibiting an "inexplicable taste for the new fibre-optic cables that are being strung along the ocean floor", said a 1987 New York Times report.

These shark attacks have forced companies such as Google to protect their underwater fibre cables by wrapping them with Kevlar.

Aside from sharks, external threats to these cables also include natural disasters, ship anchors and trawling by fishing boats.

They are also the vulnerable targets of spies and saboteurs.

During the Cold War period (1945 - 1991), the US National Security Agency conducted an operation titled "Ivy Bells" which used submarines and underwater recording pods to gather transmissions from an undersea cable connecting two of USSR's major naval bases.

In 2013, three scuba divers were apprehended by Egyptian authorities for attempting to cut through an undersea cable off the port of Alexandria.

The cable that these saboteurs targeted was the SeaWeMe-4 (South-east Asia-Middle East-Western Europe-4) cable which provided a third of Egypt's and Europe's internet capacity.

6. They are cheaper and more effective than satellites

News network CNN reported in 2015 that over 99 per cent of our international communications are still transmitted by undersea cables, even with the creation of satellites.

Satellites are known to be less effective, as it takes a longer time to transmit information to and from space compared to the data transfer speed that optical fibres in undersea cables are capable of.

Researchers have developed optical fibres that can transmit information at 99.7 per cent the speed of light, states.

Also, undersea cables are cheaper than satellites - which are also limited in capacity.

Sources: The Daily Mail Online, Infocomm Development Authority, Economic Development Board,, CNN,

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