The rapid exchange of data around the world relies on an often-overlooked infrastructure: undersea cables that connect continents and carry nearly all international internet traffic. These fiber-optic cables, laid hundreds of meters beneath the ocean, form the backbone of global connectivity, enabling everything from financial transactions to daily communications. Tomas Lamanauskas, Deputy Secretary-General of the International Telecommunication Union (ITU), highlighted their importance ahead of the Second International Submarine Cable Resilience Summit in Porto, Portugal, emphasizing the need to strengthen the resilience of this critical infrastructure as global reliance on digital networks grows.
Undersea cables have evolved from 19th-century telegraph lines to modern high-speed internet conduits capable of transmitting hundreds of terabits per second. Today, over 500 commercial submarine cables stretch approximately 1.7 million kilometers along the ocean floor, linking continents, markets, and households. These cables are relatively thin yet essential, and careful seabed surveys, environmental assessments, and specialized cable-laying ships ensure their safe deployment.
Despite their robustness, submarine cables are vulnerable to both natural and human-made disruptions. Earthquakes, underwater landslides, and volcanic activity can damage cables, but about 80% of incidents result from human activity such as ship anchors or fishing trawlers. Cable failures can have immediate consequences, affecting internet access, emergency services, financial systems, and essential services like digital healthcare and education. Remote regions, like Tonga, illustrate the vulnerability of isolated networks, where a single cable cut can leave large populations offline for extended periods.
Repairing damaged cables involves multiple challenges beyond the technical work itself. Engineers can quickly identify affected areas, but obtaining permits and coordinating across overlapping jurisdictions can delay repairs for days, weeks, or even months. Laying new cables is also time-intensive and costly, with longer lines potentially running into hundreds of millions of dollars. As cables age, with some installed around the dot-com boom reaching their 25-year lifespan, maintaining and upgrading this infrastructure becomes increasingly urgent.
While the ITU does not directly repair cables, it plays a crucial role in enhancing resilience by facilitating collaboration, setting standards, and streamlining maintenance and repair processes. The agency also promotes sustainable practices and awareness to prevent accidental damage. Over the past four decades, the capacity of submarine cables has grown exponentially, supporting the rapid expansion of the internet. Strengthening these invisible highways is essential to sustaining global connectivity, enabling economic growth, and ensuring the digital infrastructure can meet the unprecedented demands of the information age.
