Submarine internet cables, also referred to as submarine communications cables or submarine fiber optic cables, are essential infrastructure that connect different locations and data centers to reliably exchange digital information at a high speeds.
They are significant providers of global internet connectivity: approximately 99% of international communications pass through submarine fiber optic cables,Nystro, M., Jouffray, J.B., Blasiak, R., & Norstro, A.V. (2020). The Blue Acceleration: The Trajectory of Human Expansion into the Ocean. One Earth, 2(1), p43–54. along with US$10 trillion in daily financial transactions.Guilfoyle, D., Paige, T., & McLaughlin, R. (2022). The final frontier of cyberspace: the seabed beyond national jurisdiction and the protection of submarine cables. International & Comparative Law Quarterly, 71(3), p657-696. The European Union (EU), in particular, has a strong demand for connectivity, with 87% of EU citizens using the internet in 2021.World Bank. (2021). Individuals using the internet. Accessed: 03 May 2023.
Network description External network As of May 2023, the EU maintains direct connections via submarine cables to several regions:TeleGeography. Submarine cable map. Accessed: 04 May 2023. North America: 9 undersea cables (Dunant, MAREA, Apollo, Grace Hopper, FLAG Atlantic-1, AC-1, AEC-1, AEC-2, EXA Express, EXA North and South). One cable (Amitié) is being currently installed. South and East Asia: 8 undersea cables (PEACE, AAE-1, SeaMeWe-3, SeaMeWe-4, SeaMeWe-5, IMEWE, Europe India Gateway, FEA). Four cables are under installation (SeaMeWe-6, Africa-1, 2Africa, IEX). MENA region: 27 undersea cables. All cables going to Asia are also connected to the MENA region. Other cables are TE North, MedNautilus, Hawk, ORVAL, Estepona-Tetouan, Atlas Offshore, Canalink, EllaLink, Med Cable Network, KELTRA-2, Didon, HANNIBAL system, Italy-Libya, Silphium, UGARIT, Turcyos-1, Turcyos-2, CADMOS, KAFOS. 3 are being installed (Blue, Medusa submarine cable system, CADMOS-2). West, Eastern and South Africa: 5 undersea cables (SAT-3, MainOne, ACE, Equiano, PEACE). Two cables are under installation (2Africa, Africa-1). South America: 1 undersea cable (EllaLink). Oceania: 1 undersea cable (SeaMeWe-3).
The EU is also highly connected to the United Kingdom (UK), with 23 undersea cables linking the two. Although the EU lost a number of connections with North America following Brexit in 2016, it remains resilient due to strong collaboration and robust infrastructure independent of the UK.Bueger, C., Liebetrau, T., & Franken, J. (2022, June). Security threats to undersea communications cables and infrastructures – consequences for the EU. EU Parliament.
Internal network As of May 2023, the EU had 39 undersea cables connecting Member States exclusively. with three more under installation (Digital E4, Eastern Light Sweden-Finland II, Ionian). These cables mostly connect island states such as Malta or countries bordering the Baltic Sea.
Northern Europe (31 cables): COBRAcable, GlobalConnect 2, Kattegat 2, Denmark-Sweden 16, Denmark-Sweden 17, Denmark-Sweden 18, Scandinavian Ring North, Scandinavian Ring South, Danica North, IP-Only Denmark-Sweden, Baltica, NordBalt, Latvia-Sweden 1, Sweden-Latvia, Baltic Sea Submarine cable, Eastern Light Sweden-Finland I, BCS North-Phase 1, Sweden-Finland 4, Sweden-Finland Link, Sweden-Estonia, C-Lion1, Finland-Estonia 2, Finland-Estonia 3, Finland-Estonia connection, Botnia, BCS East, BCS East-West Interlink, Denmark-Poland 2, Germany-Denmark 3, GlobalConnect-KPN, Fehmarn Bält. Southern Europe (8 cables): Malta-Italy Interconnector, Melita 1, Epic Malta-Sicily Cable System, Italy-Malta, GO-1 Mediterranean Cable System, Italy-Greece 1, OTEGlobe Kokkini-Bari, Italy-Croatia.
Legal and Regulatory Framework
International law The legal framework governing submarine internet cables is principally the United Nations Convention on the Law of the Sea (UNCLOS).Burnett, D.R., Beckman, R., & Davenport, T.M. (2013). Submarine Cables: the Handbook of Law and Policy. Brill, p74-88. Although research and development of the internet's physical infrastructure progressed during the 1970s, the internet and its underlying cable infrastructure came into widespread use only after UNCLOS was adopted in 1982.
Laying cables is part of the "freedom of the seas" (Article 87). Submarine cables are authorized everywhere except within territorial waters, where coastal states have sovereignty and may enforce their regulations. The laying, maintenance and repair of cables must consider existing infrastructure and respect the exclusive economic zones (EEZ) of coastal states (Article 79).Davenport, T. (2015). 'Submarine Communications Cables and Science: A new Frontier in Ocean Governance?', in Scheiber, H., Kraska, J., Kwon, M. (eds). Science, Technology, and New Challenges to Ocean Law. Brill
Ownership of submarine cables is primarily private, mostly by telecommunications companies.Wall, C., Morcos, P. (2021, June 11). 'Invisible and Vital: Undersea Cables and Transatlantic Security' with increasing investments by technology firms such as Meta and Google. Most cables are owned and managed by consortia of companies. Under UNCLOS, owners are liable for damages to cables (Article 114). They must also compensate fishermen or ships for damage caused by cable protection measures (Article 115). States are obliged to criminalize intentional damage to submarine cables (Article 113), except when necessary to protect lives or ships.
With growing concerns climate change and environmental impacts, sustainable protection of submarine cables is a developing priority, though UNCLOS currently lacks mandatory enforcement mechanisms.You, Y. (2011). 'Using Submarine Communications Networks to Monitor the Climate – an ITU-T Technology Watch Report"
The European Union Initially, regulation of cyberspace and internet infrastructure in the EU was left largely to private companies, reflecting an early philosophy of the internet as "free" space, influenced heavily by the United States.Claessen, E. (2020). Reshaping the internet – the impact of the securitisation of internet infrastructure on approaches to internet governance: the case of Russia and the EU, Journal of Cyber Policy, 5(1), p140-157. This approach shifted following cyberattacks on European governments (Estonia in 2007, Georgia in 2008), leading to increased state and EU involvement.
Given the importance of connectivity, especially with five Member States (France, Denmark, Italy, Portugal and Spain) as major contributors, the EU has recently recognized submarine internet cables as strategic and geopolitical assets.Bueger, C., Liebetrau, T., Franken, J. (2022, June). 'Security threats to undersea communications cables and infrastructure – consequences for the EU. European Parliament The Russo-Ukrainian War, and incidents such as the Nord Stream pipeline attack have further highlighted this importance.
However, submarine cable protection has not been a top priority; maritime security efforts focus more on piracy, people smuggling, and environmental issues.Long, R. (2015). "A European Law Perspective: Science, Technology, and New Challenges to Ocean Law". In: Scheiber, H., Kraska, J., Kwon, M-S. (2015). Science, Technology, and New Challenges to Ocean Law. Fisheries, significant in certain EU countries, are linked to cable protection but have often viewed it as a lesser concern.
Responsibility for cable protection generally resides with national governments. According to the 2023 report by the European Union Agency for Cybersecurity (ENISA), regulatory regimes vary: France: The Secretariat-General for National Defence and Security, the Secretariat-General of the Sea, and the French Navy oversee cable protection with companies like Orange Marine conducting maintenance.ENISA. (2023, July). 'Subsea Cables – What is at stake?' Portugal: Multiple agencies, coordinated by the National Communications Authority (ANACOM), manage cable permits and monitoring, including alert systems for ships near cable routes.Raha, U. K., Raju, K. D. (2021). Submarine Cables Protection and Regulations: A Comparative Analysis and Model Framework. Other countries (e.g.,Bulgaria, Sweden): Private cable owners assume responsibility for security.
Internet cables were not classified as Critical Infrastructure in the 2008 European Programme for Critical Infrastructure Protection(EPCIP),Council of the European Union. (2008, December 8). Council directive 2008/114/EC of 8 December 2008 on the identification and designation of European critical infrastructures and the assessment of the need to improve their protection. Annex I. but the 2013 update recognized cyberspace as a growing concern.European Commission. (2012, June 22). Commission staff working document on the review of the European Programme for Critical Infrastructure Protection (EPCIP) Today, submarine cables are categorized under "information and communication systems" critical infrastructure by the EU.European Commission. Critical infrastructure protection. Accessed: 20 May 2023.
Threats Submarine internet cables are subject to threats and damages of different kinds, to which the EU is more or less vulnerable. Three categories can be distinguished: natural causes, unintentional human causes and intentional human causes.
Natural threats The first kind of damages to internet cables are natural hazards. Overall, they account for less than 10% of all submarine internet cables damages. Natural hazards comprise:
Shark/fish bites. There is no consensus as to why sharks bite undersea cables. Hypotheses are curiosity, or confusion with food due to the cables’ electric field (similar to electromagnetic fields sensed from their preys).Márquez, M.C. (2020, July 20). Our underwater world is full of cables… that are sometimes attacked by sharks. Forbes. Accessed: 10 May 2023. They remain a marginal threat: fish bite accounts for only 0.5% of cable faults over the period 1959–2006.Sunak, R. (2017). Undersea cables. Indispensable, insecure. Policy exchange. p21. They are mainly a concern for consortiums and not for the EU, as traffic can easily go through another path. Google declared in 2014 that they would wrap at least a part of their submarine internet cables, made of fibre, in Kevlar-like material to protect them.Butler, B. (2014, August 13). Google wraps its trans-Pacific fiber cables in Kevlar to prevent against shark attacks. Network World. Accessed: 10 May 2023. This kind of measures, as well as cable burials in the seabed, made that no damaging fish bites were reported over 2007–2014.International Cable Protection Committee. (2015, July 1). Sharks are not the Nemesis of the internet – ICPC findings Abrasion. Abrasion mainly happens when there are wave activities, currents, or when cables are laid on rock. It is a more predictable phenomenon, which is why scientists try to identify its conditions and develop protections. It was responsible for 3.7% of cables faults over 1959–2006. Natural disasters (volcano eruptions, earthquakes, tsunamis). They mostly happen in geologically unstable areas, which are outside the EU – even though there is a seismic risk in the Balkans, Greece, and Italy. The danger of such events is to break several cables at the same time, making it harder or impossible to circumvent data through another path. Natural disasters especially represent a major threat to island states, because they are geographically more exposed and because they are often poorly connected. Recent examples of massive internet interruptions are Typhoon Morakot (2009) or the 2022 Tonga volcano eruption.