Currently, submarine cables are responsible for 99% of the transoceanic communications (between locations separated by an ocean) made worldwide. With optical fiber, cables can transmit data such as voice, images and messages.
They are buried up to 1,000 meters deep in the ocean with a metallic duct liner. This prevents damage from shark attacks or fishing boats. In deeper regions, where the risk is lower, the cables are thinner.
Installation is carried out by a ship. Before, however, an instrument attached to the vessel created cracks in the land at the bottom of the ocean, where the cable will be deposited. The process takes time: just wrapping the cable up to put it on the ship can take three weeks.
Submarine cables have a number of advantages over satellites: heavy rain and typhoons are unable to affect their signal and data traffic is up to 1,000 times greater than that of the satellite.
This means that the optical fiber can transmit the equivalent of what fits on 102 DVDs in one second. Satellites, on the other hand, cannot even send the contents of a DVD in the same period of time - and still require the signal to travel a greater distance to connect two locations. Other than that, satellites also have latency problems, which is the time it takes for information to reach its destination.
The animals at the bottom of the sea end up interacting with the underwater cables. For this reason, the equipment receives a protection reinforcement in shallow waters.
