Submarine cables are the backbone of today’s Internet

In our globalized and interconnected world, around 99% of all exchanges of data are enabled by fiber optic submarine cable systems.

This critical infrastructure forms the backbone of the Internet, even though it remains largely invisible to the end-user due to its underwater nature… Inscribed in a multi-secular social and technical history (since the mid-XIX century), submarine cables remain important and form a complex capillary system connecting multiple countries around the globe.

Satellites are sometimes thought to form the majority of internet infrastructure, allowing us to enjoy a performant internet access all around the world, whether it be in the middle of the Pacific Ocean or on the top of the Everest Mount. Although, satellites do provide Internet access in remote and difficult to reach areas, submarine cables still provide the most efficient and fastest telecoms infrastructure.

Terms such as “cloud application”, “virtual server” or “wireless world” tend to keep away, whether intentionally or not, the importance of the submarine efficiency. However, satellites are much less technically efficient.  A simple way to think about this is to compare the units used to measure the capacity of the telecoms infrastructures:  for the satellite bandwidth we talk about Gigabits per second (GB/s), while many submarine cables are designed to have a capacity of several Terabits per second (TB/s). For example, the EllaLink cable provide 25 TB/s per fiber pair between a server in Europe (Sines, Portugal) and a server in Latin America (Fortaleza, Brazil), with a latency of less than 60 milliseconds.