05 Sep What is submarine fibre and how does it connect continents? The invisible ‘backbone’ of the internet

When we browse the internet, send an email, or make a transcontinental video call, we rarely think about the physical infrastructure that makes it possible. However, behind the immediacy of global connectivity lies a gigantic, silent network, invisible to most: submarine fibre optic cables. These cables are the internet’s ‘backbone’, the spine that transports almost 99% of all the world’s data traffic. Their importance as critical infrastructure is undeniable, as they are the true bridge that connects continents. 

What are submarine fibre optic cables and their importance 

Submarine fibre optic cables are thin filaments of glass the thickness of a hair, grouped into a much thicker cable and protected by several layers of insulating materials and steel armouring. Their main function is to transmit data in the form of light pulses, at astonishing speeds and with unimaginable capacity.  

While terrestrial networks connect cities and countries, submarine cables link entire continents and regions, forming the basis of the modern internet. Without them, global communication would be slow, inefficient, and extremely expensive, relying on less reliable technologies like satellites, which have much greater latency. These cables are, in essence, our planet’s information superhighway. 

How they are installed and where they pass: the routes of global connectivity

The installation of these cables is a monumental engineering project. It is carried out using specialised cable-laying ships, which transport the cable wound on enormous spools. The process involves depositing the cable on the seabed, following carefully planned routes that avoid areas of high seismic risk, underwater volcanoes, or intensive fishing routes. Near the coast, the cable is buried to protect it from ship anchors and other human activities. 

The network of submarine cables is not random; it follows strategic routes that connect points with the highest data demand, from large financial and technological hubs in North America, Europe, and Asia, to emerging regions in Africa and Latin America. Each cable is an international collaboration project, with multiple companies and countries investing to ensure connectivity and redundancy in their routes. 

The protection of a critical infrastructure: maintenance challenges 

Protecting and maintaining such a vast and vital network is a constant challenge. Despite efforts to bury the cables near coastlines and avoid the highest-risk areas, incidents do happen. The main cause of damage to submarine cables is not sharks or extreme natural phenomena, but human activities, primarily the dragging of large ship anchors and trawl fishing nets.  

Maintaining these cables is a complex operation that requires the use of submarine robots and repair ships. Faults, while temporary, can affect connectivity across entire regions, which underscores the importance of having a robust infrastructure with multiple alternative routes to guarantee network resilience. Investing in their security and maintenance is essential for the stability of the global digital economy. 

Conclusion: lyntia, the commitment to the invisible ‘backbone’ 

Submarine fibre optic cables are the pillar of global connectivity. They are the infrastructure that makes possible the immediacy of communication, digital commerce, and social interaction on a global scale. To understand their role is to recognise the complexity and criticality of the infrastructure that, at lyntia, we are dedicated to building and maintaining. Our commitment to deploying and interconnecting high-capacity networks is fundamental to ensuring that this invisible ‘backbone’ continues to function efficiently, robustly, and securely, guaranteeing that the digital future is accessible to everyone, everywhere.