Nowadays, global telecommunication is vital for business and politics. Information are exchanged and transmitted in speed of light around the globe. Though hundreds of satellites in the Earth orbit handle a part of the telecommunication, undersea cables carry about 95% of the world’s Internet and telephone traffic. These fiber optic cables can transmit more data by pulses of light from a laser and are cheaper than satellite communication. However, it takes a lot of effort to build up, extend and maintain the global undersea cable network. To protect the fragile wire from the hostile conditions it faces under the sea, it is wrapped into a protective and waterproof coating of steel and plastic. The cables run through oceans and link all continents except Antarctica. To make it fit into the contours of the ocean bed and to use it as efficiently as possible, a lot of surveying is necessary before the deploying process can begin.
Despite all protective efforts, undersea cables are damaged or cut from time to time. In most cases, fishing trawlers or anchors cause the cables to break. Severe disruptions also can occur when a heavy earthquake damages the cables. But when a series of outages affected three cables in the middle east early this year in one week, suspicions arose that the cables could have been cut deliberately. Whether the disruptions in the Suez channel were accidents or not, the undersea cable network is a potential target for attacks and permanent surveillance is not possible. Cables near the coast are buried in the seabed and are vulnerable – either to damage from ships’ anchors, trawl nets or deliberate breakdown.
If a cable is damaged, the Internet traffic is detoured to alternate routs which slows down the speed and repairing the cable is very expensive and elaborate. The impact of disruptions is felt most by those in the area of the disrupted cable – sometimes whole countries are cut off from the Internet – but even thousands of kilometers away the disruption can lead to a slowdown in Internet traffic.
A map of undersea cables from Alcatel-Lucent: