Subsea Cables as Critical Infrastructure

This episode, presented by the German Maritime Centre, explores the essential role of subsea cables as critical infrastructure underpinning global communications and business operations. Host Matthias Catón is joined by guests Camino Cavanagh and Jonas Franken, both experts in cyber security, international security, and maritime systems.

What Are Subsea Cables?

Subsea cables are fiber-optic systems laid across the seabed, connecting continents and islands for data transmission. They include not only the cables themselves but also landing stations, maintenance ships, repair logistics, and complex terrestrial links. The technology has advanced from telegraph cables to modern fiber optics, forming a backbone for the internet and communications.

Scale and Complexity

There are currently around 530 active international cable systems, with 70 more in the planning stages. Some cables connect just two points, while others are complex networks with up to 30 landing stations. Globally, over 1,600 cable landing stations exist, varying in size and complexity.

Visibility and Public Awareness

While most people rarely notice subsea cables, outages in places like Tonga, Southeast Asia, Norway, Ireland, and the Shetland Islands have raised awareness. Many still mistakenly believe internet connectivity is reliant on satellites, while in reality, subsea cables handle the overwhelming majority of data traffic.

Redundancy and Resilience

European countries enjoy high redundancy, ensuring minimal disruption from cable faults. In contrast, remote nations often rely on a single cable, making them more vulnerable to outages. Subsea cables are engineered for resilience, with backup options usually available, though incidents can still affect connectivity.

Satellite vs. Subsea Cables

Satellites serve a supplementary role, but subsea cables provide vastly superior bandwidth and lower latency. Even with modern satellite networks like Starlink, they cannot match the data volume or speed required for global internet infrastructure.

Ownership and Financing Models

Ownership is diverse:

Major content providers such as Google, Meta, Amazon, and Microsoft, either individually or through consortia.
Traditional telecom companies in consortia.
Direct state involvement, including military-operated cables.
Development bank funding—sometimes as part of diplomatic efforts.

The European Union and the US are introducing more regulations, affecting industry operations.

Business Implications

Businesses—especially large, data-reliant firms—should consider cable resilience as part of their risk management. Industry groups such as the International Cable Protection Committee and the European Subsea Cable Association foster collaboration and dialogue. Medium and smaller businesses may face challenges in influencing infrastructure policy, but are equally reliant on connectivity.

Regulatory Trends

Regulation is increasing, especially across the EU (NIS2 Directive, Critical Entities Resilience Act) and the US (Federal Communications Commission rules). The challenge for policymakers and industry is to balance demanding security requirements with the need for operational flexibility and rapid response.

Geopolitical Competition and Strategic Concerns

Subsea cable networks are increasingly central in international competition, including concerns about reliance on equipment from certain foreign suppliers, particularly China. Security requirements may slow cable operations just when agility is needed most.

Looking Ahead: Bold Predictions

Jonas Franken predicts Antarctica will be connected to the subsea cable network in the next decade, marking symbolic global connectivity.
Camino Cavanagh foresees subsea cables becoming even more contested and central to state competition, with industry facing greater challenges ahead.

Conclusion

Subsea cables are a crucial, yet often invisible, part of global infrastructure. Businesses and governments must increasingly account for resilience, security, and redundancy, given their importance to society and the economy. The episode emphasizes the need for awareness, collaboration, and proactive planning as the geopolitical and regulatory landscape evolves.

About the guests

Jonas Franken

Jonas Franken is doctoral candidate at Science and Technology for Peace and Security (PEASEC) in the Department of Computer Science at the Technical University of Darmstadt. His research interests are located within the nexus of policy, technology, and international law, focusing on the resilience of Critical Information Infrastructures on land and at sea, as well as emerging problems in Maritime Security and the digitalization of Critical Infrastructures. He studied “Politics & Law” (B.A.) at the University of Münster and holds a Master’s degree in “International Studies / Peace and Conflict Research” (M.A.) from Goethe University Frankfurt, and Technical University of Darmstadt. The former member of the German Navy was for a long time engaged in civilian sea rescue.

Website: https://peasec.de/team/franken/
LinkedIn: https://www.linkedin.com/in/jonas-franken-711a6b147/
Bluesky: https://bsky.app/profile/jonasfranken.bsky.social

Camino Kavanagh

Camino Kavanagh is a visiting Senior Fellow with the Dept. of War Studies, King’s College London and a Fellow with the United Nations Institute for Disarmament Research (UNIDIR). Her research covers topics relevant to technology, international security, conflict and diplomacy. Her current work focuses on cybersecurity and on the security and resilience of subsea infrastructure. Amongst other, Camino served as advisor/rapporteur to the 2019-2021 and 2016-2017 UN negotiating processes on cyberspace/ICTs and international security (the UN Open Ended Working Group and the UN Group of Governmental Experts). For the past decade she has also worked extensively across United Nations peace and security entities, with regional organisations and national governments on issues pertaining to international peace and security, conflict and digital technologies. Prior to this, Camino spent over a decade working in conflict contexts around the world, including with UN peacekeeping operations and political missions.

LinkedIn: https://www.linkedin.com/in/caminokavanagh/

Executive Briefing – what you should read now

Nicole Starosielski, The Undersea Network (Sign, Storage, Transmission), 2015, Durham, NC and London, UK: Duke University Press.

José Chesnoy, Jean-Christophe Antona (Eds.) Undersea Fiber Communication Systems 3rd Edition, 2025. Academic Press.

C. Kavanagh, J. Franken, and W. He. “Achieving Depth: Subsea Telecommunications Cables as Critical Infrastructure”. Geneva, Switzerland: UNIDIR, 2025.

Omand, David: How to Survive a Crisis: Lessons in Resilience and Avoiding Disaster, 2023. Viking.