Submarine cables around the world
Submarine cables carry 95% of digital data from around the world. But, after all, what is the nature of this mysterious technology?
The series of sabotage attacks on submarine cables in the Baltic Sea, which have been multiplied in recent months, has sounded the alarm in the organization of the North Atlantic Treaty (NATO) and exposed the vulnerability of global energy and telecommunications infrastructures.
Between November and January, several electrical, internet and telephone cables were cut to Finland to Estonia, Finland to Germany, Latvia and Sweden – with damage that also affected other Baltic countries.
A principal Suspect falls on Russia’s “ghost fleet”consisting of old oil tankers carrying oil from Russia, surrounding sanctions against the country. NATO believes that ships drag anchors to damage connections at the bottom of the sea.
As a note, understanding how the world system of energy and telecommunications depends on the integrity of submarine cables.
Different types of underwater capes
Some submarine cables carry direct current electricity of high voltage (HVDC) to long distances, between islands or countries. Can also be used to connect wind turbines offshore to terrestrial sites.
Os telecommunications cableson the other hand, they transmit about 95% of global data trafficincluding simple orders such as internet searches, line purchases and telephone calls. Data transmission is done in record time, although with a slight signal delay: accessing a US website from Europe takes about 60 milliseconds (0.006 seconds).
In addition, there are cables that connect data centers and large network nodes – Terminals that drive data traffic.
Other cables, more protected, are conceived exclusively for the transfer of Military and Research Communications.
Satellites are not an alternative
Only a fraction of international communications is made via satellite – the cables Submarines can transmit much more data at a lower cost. Satellite bonds are slower and more susceptible to interference.
Even so, the US and the European Union (EU) are investing in satellite technologies, such as those provided by Starlink and the Resilience Infrastructure, Interconnectivity and Satellite Safety Program (Iris), to create alternative communication channels and more insurance.
Where are they located?
Around the worldthere are about 500 lines, totaling 1.4 million kilometers of cables. They are so long that they could surround Ecuador 30 times, and Every year new cables are added.
Most calls are located In the Atlantic Oceanbetween Europe and North America, and No peacefulbetween the US and East Asia.
However, there is no full global Atlas that shows the exact location of all cables. Platforms such as O or Offer Maps, but without exact information about the location.
About 90% of data traffic between Europe and Asia passes 14 cables off the coast of Yemen. In 2024, the rebels Houthi They attacked maritime traffic and three lines of data using a hijacking cargo ship in the region.
Who installs the cables?
In the past, telecommunications operators, such as AT&T and China Telecomm, dominated the market and ownership of these lines of communication. Currently large technological companies such as Googlea Microsofta Meta and Amazon They are investing strongly in this model.
Google currently has six active submarine cables and plans to install others. The goal has a participation in 16 existing cables and plans to create its own global network.
How are they built?
Modern submarine cables consist of several layers of fiber optics that use light impulses to transmit digital information. They are surrounded by protective layers of steel wires or steel, polyethylene and waterproof materials.
This protects them against extreme pressure and adverse conditions of the seabed, ensuring a Life of about 25 years. Large submarine cables, with a diameter of over 20 centimeters, can weigh between 40 and 70 kilos per meter.
How are they installed?
Geologists and engineers determine the best places to put the cables, taking into account obstacles such as ocean trenches, sea currents, fishing zones and sea routes.
In the North Sea and the Baltic Sea, about 1.6 million tons of past warm ammunition also represent a major challenge in the sea. In deep water, up to eight kilometers, the risk of damage is lower. The cables are usually placed directly on the seabed by special ships.
Or end needs to be tensioned during the installation process. If the voltage is insufficient, ties may form. If the voltage is too high, the cable can float and leave.
Damage in submarine cables
Most damage to submarine cables are caused by drag nets and anchors. But they are also the target of deliberate acts of sabotage. Hybrid war attacks have been known since the Cold War.
In 1959, the United States accused the Soviet Union of intentionally damaging a submarine cable with fishing nets.
Espionage is also a serious problem, since the cables can be intercet for data collection.
How are they repaired?
Repair of submarine cables is a complicated process due to extreme underwater pressure and unpredictable weather circumstances.
Depending on the damage and depth of the cable, the divers can perform Repairs in dried chambers.
Or one cable repair ship can carefully to the surface. On board, technicians replace sections damaged by new ones. After exhausting tests, the cable is carefully repositioned at the bottom of the sea.
How are they protected?
Submarine cables are well protected against natural weather conditions, but are not strong enough against deliberate damage caused by terrorism. You submarine drones and acoustic sensor systems They can help detect potential acts of sabotage in advance.
Some countries are developing coordinated protection strategies, with close cooperation between governments, underwater cable operators and international organizations. Experts appeal to the creation of new legal frameworks at national and international level, especially for war cases.
