can Russia cut off the internet in France by attacking the submarine cables?

The war in Ukraine highlights an area as sensitive as it is little known: the seabed. Today, they host in their depths more than 400 cables that connect the continents by providing them with nothing less than 99% of Internet traffic.

In Europe, the route that concentrates all the attention is that of the Atlantic since 80% of our Internet exchanges are carried out with the United States. For financial transactions, emails, calls, apps, personal and business files that we sometimes store unknowingly on servers across the Atlantic. We access it by borrowing every day, every hour, submarine cables.

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These fiber optic cables are valuable in our daily lives and for our economy. They are also very expensive: several hundred million euros each. Telecom operators organize themselves in consortium with Gafam like Facebook or Google to finance and file them.

Is it easy for a foreign power to interfere with these cables? Yes since they are no bigger than a garden hose. It therefore appears very easy to cut them. France is connected by 51 submarine cables, some are more powerful than others and are called “megacables”. “It is enough to break two or three of these megacables for France to find itself in an extremely difficult situation”, says Jean-Luc Vuillemin, director of international networks at Orange.

In the open sea, the exact position of the cables is not known to the public. But it can be communicated to third parties such as boats so that they do not collide with these installations. Information can therefore easily find its way into the hostile hands of a foreign power. A subject of concern for Orange in the context of the conflict that we are experiencing. The operator is a stakeholder in 40 submarine cable consortia.

“The Russians have been interested in these cables for a long time, continues Jean-Luc Vuillemin. We have identified a spy ship attached to the Russian Ministry of Defense as well as a class of submarines with deep intervention capabilities. These means are geolocated extremely frequently on points of concentration of submarine cables.

For the Ministry of the Armed Forces, which presented its so-called “seabed control” strategy in mid-February, “the seabed constitutes a new field of conflict in the same way as cyberspace and the informational sphere”. The French Navy is responsible for monitoring the cables 365 days a year, in territorial waters as well as in international waters.

For the institution, the Russian threat is judged “credible”, according to Captain Eric Lavault. “The job of the military is to plan and consider all the hypotheses. This hypothesis is part of it even if we do not attribute any intentions to Russia at this stage. But we are preparing.”

However, it is impossible for the armies to be present on the different seas at the same time and to operate the protection of all these cables which account for a cumulative distance of more than a million kilometres. Cables also lie several thousand meters deep and the French Navy does not yet have the necessary equipment to access these depths.

“I have therefore taken the decision to provide our armies with means capable of reaching 6000 meters. 6000 meters, this makes it possible to cover 97% of the seabed and to effectively protect our interests”announced the Minister of the Armed Forces, Florence Parly, presenting her strategy on February 14, ten days before the war in Ukraine broke out.

The question then arises of the repercussions for Russia itself of attacking these infrastructures. Experts consider that the consequences would be quite small since Moscow has relocated the servers it needs to its territory in recent years. Its stated desire is to be self-sufficient in this area in the long term. The country also has its own applications and its national search engine, Yandex.

Conversely, France is dependent on servers abroad, Gafam and therefore submarine cables. “The characteristic of a cable is that it can be cut, says Alexandre Schon, doctor in the geography of telecommunications. Instead of spending astronomical sums in monitoring these cables, it could be wise to increase the resilience of our networks by imagining autonomous ecosystems”.

For the researcher, the war in Ukraine but also the campaign for the presidential election in France must be an opportunity to question the thousands of data that individuals, companies and administrations generate on a daily basis: where do they host them? o and to which private actors do we decide to entrust its management?