Ever wonder how we get our internet? What infrastructure is in place for us to be able to watch cat videos, post beloved photos and read the latest news online? Connecting Australia to the rest of the world is done mostly via undersea cables.

Fibre Cables

Almost all trans-oceanic Internet data exchanges are via undersea cables, replacing satellites as the preferred medium. Google and a group of telecommunications companies invested in one of them, and named this new undersea cable system FASTER. FASTER will stretch across the 9,000 kms between the United States and Japan, and is estimated to be completed by mid 2016.

FASTER will be designed with 6-fiber-pair cable and optical transmission technologies with an initial capacity of 60Tb/s. Sixty terabits per second, which is about 10 million times faster than a standard cable modem!

Here are some things to know about FASTER and undersea cables:

The optical fibres at the heart of the cable are made of highly purified glass that’s as thin as a human hair. Internal reflection is used to guide light along the path of the fibre.

Some undersea cables can carry up to 80 Tb/s, which is the equivalent to transmitting 2,100 DVDs (4.7 GB each) in one second, according to NEC.

Undersea Cable - Internet

At 39,000 km long, the South East Asia Middle East Western Europe 3 network stretches from Western Europe to Australia and East Asia, linking 33 countries and four continents. (see pictured)
About 99 percent of all trans-oceanic Internet data is sent via undersea cables. Back in 1995, about half of this traffic went through satellite which require data to travel far greater distances. Hundreds of undersea cables link parts of the world together and satellites are still used today to connect to remote areas.

In 2013, undersea cables carried 51 billion gigabytes per month and this is expected to increase to 132 billion gigabytes in another four years.

Undersea cables have to withstand pressures of 8 km of water on top of them (imagine putting an elephant on your thumb!), yet the typical lightweight polyethylene cable for deep oceans for FASTER, is only 17 millimeters thick.

You may have heard the theory about how the majority of internet outages are due to sharks damaging undersea cables. In fact, sharks and other sea creatures are only responsible for less than 1% of all undersea cable faults up to 2006. This sneaky shark is part of that one percent, and can be seen here gnawing on an undersea cable!

The production of the FASTER cable is at OCC, the fiber is first embedded in a jelly compound to keep water out in case the cable is damaged. It is then encased in a steel tube to protect it from the water pressure it will need to withstand. The fibre is then wrapped in steel wire for strength, then followed by a copper tube to hold the wires all together. The final layer to make the cable is usually made out of polyethylene to make the undersea cable resistant to water.

In areas where the cable may need more protection, OCC can create “armour” for the undersea cable. The cable can be protected by either a single armour or a double armour casing. The single armour method involves taking the existing cable, adding more steel wires for strength, then an asphalt coating to prevent corrosion, plastic strings to cover the asphalt and chalk powder to prevent the cable from sticking to itself. The same process is repeated for the double armour version.