Critical undersea infrastructure – subsea cables, pipelines, data links, and energy connectors – has become one of the most essential yet vulnerable layers of the modern global system. More than 95% of the world’s internet traffic and trillions of dollars in financial transactions flow through these seabed networks. Damage to even a single cable can shut down communications across regions, disrupt markets, or impair government operations.
This reality was front and center at the NATO Critical Undersea Infrastructure (CUI) Network meeting held in Rome in November 2025. The gathering brought together military leaders, civilian agencies, industry stakeholders, European Union representatives, and partner nations to strengthen coordination and share best practices.
The meeting highlighted the rapid rise of hybrid threats across Europe and the Mediterranean. Participants examined ways to secure undersea assets using sensing and surveillance technologies – including underwater drones, seabed sensors, and advanced maritime monitoring systems. A visit to the Italian Navy’s CUI Surveillance Center showcased how integrated civilian/military operations can support rapid detection and response to suspicious underwater activity.
As NATO Assistant Secretary General Jean-Charles Ellermann-Kingombe noted, “A 360-degree approach to security is vital for the Alliance. The Mediterranean region could not be more critical.” Recognizing that threats span physical sabotage, cyber intrusions, environmental hazards, and geopolitical competition, the Alliance emphasized the need for deeper information sharing and coordinated action.
This blog explores the evolving landscape of critical underwater infrastructure, including major initiatives, global opportunities, emerging threats, and the market concerns shaping investment and security planning worldwide.
Evolution of undersea infrastructure
While today’s subsea networks are technologically advanced, their origins stretch back more than 165 years. The first transatlantic telegraph cable was laid in 1858, connecting Europe and North America with copper wire insulated in gutta-percha. These early systems were limited, fragile, and difficult to repair.
Today, more than 550 active submarine cable systems span more than 1.4 million kilometres, carrying hundreds of terabits of data per second through multi-strand fibre-optic technologies. Subsea pipelines transport oil, gas, electricity, and hydrogen between continents, supporting energy security and economic interdependence.
This transformation has increased both capability and strategic importance. At the same time, it has expanded operational complexity, environmental considerations, and geopolitical vulnerability, making modern protection efforts far more urgent.
Initiatives: opportunities and global efforts
Modernizing and securing critical underwater infrastructure is now a strategic priority across the public and private sectors. As global demand for high-capacity data and secure energy distribution grows, nations and alliances are investing in technologies and partnerships that strengthen resilience, surveillance, and coordinated response.
At the NATO CUI-Network meeting in Rome, stakeholders highlighted how advanced sensing technologies can enhance monitoring and early warning systems. Autonomous underwater vehicles, unmanned surface vessels, seabed acoustic arrays, and satellite-based surveillance tools provide continuous coverage in areas where crewed patrols are limited.
Governance frameworks shape how infrastructure is built, regulated, and protected. Key organizations include the International Telecommunication Union (ITU), which sets technical standards; the International Cable Protection Committee (ICPC), which coordinates industry best practices; the International Seabed Authority (ISA), which oversees seabed use beyond national jurisdictions; and national regulators responsible for cybersecurity, environmental compliance, and permitting.
Environmental considerations influence planning and construction. Cable routes must comply with environmental impact assessments, restrictions on marine protected areas, and biodiversity conservation requirements. Increasingly, operators integrate seabed mapping and ecological modelling to minimize disruption to marine habitats.
Notable recent initiatives
- Launch of NATO Maritime Centre for the Security of Critical Undersea Infrastructure to enhance allied coordination, shared intelligence, and rapid response capabilities:
- Event summary of Asia Pacific Foundation – Democratic Resilience and Maritime Security Program – Highlights the vulnerabilities of the Indo-Pacific cable and promotes cross-regional cooperation.
- Strengthening of Singapore–Netherlands Undersea Infrastructure Protection Partnership is another model for bilateral collaboration on surveillance and emergency response.
These global initiatives reflect a growing recognition that protecting underwater infrastructure is essential for digital connectivity, economic continuity, and national security.
Notable threats and risks
Critical undersea infrastructure faces an increasingly complex threat landscape shaped by physical interference, cyber vulnerability, environmental pressures, and hybrid geopolitical activity. Climate change exacerbates these risks, with stronger storms, shifting seabed conditions, and new Arctic navigation routes bring greater exposure to sensitive areas.
Repairing damaged infrastructure is costly and time-sensitive. Only about 60 specialized cable-repair vessels exist worldwide, creating significant bottlenecks during emergencies. A single repair can cost up to $5 million USD, with outages lasting anywhere from several days to several weeks, depending on depth, distance, and weather conditions. These challenges are magnified in remote and environmentally restricted areas where access is limited.
Hybrid threats continue to rise. State-backed actors conduct covert seabed mapping, deploy underwater vehicles, manipulate vessel transponders, and test the resilience of cable landing stations through cyber probes. These activities often occur in international waters, creating legal ambiguity and complicating enforcement and attribution.
Environmental regulations also influence how and where operators can perform maintenance. Marine-protected areas, habitat conservation laws, and fisheries policies can restrict vessel movement or require additional assessments before repairs can begin.
Recent risks and market concerns
- Covert mapping, surveillance, and tampering by state actors have increased significantly, often involving disguised vessels or unmanned underwater drones.
- Intentional cuts and interference have occurred in politically sensitive regions, disrupting communications and exposing gaps in response coordination.
- Bottom-trawling and anchoring remain the leading causes of cable breaks, resulting in costly repairs and operational downtime.
- Suspicious vessel activity in chokepoints including AIS spoofing, loitering, and non-movement drifting over known cable routes raise security concerns.
- Cyber intrusion into digitized cable-landing stations and sensor networks is increasingly vulnerable to cyber intrusion, data manipulation, or remote sabotage.
- Repair capacity constraints with few specialized repair vessels globally, multiple incidents could overwhelm available capacity and prolong outages.
- Communication disruptions impact financial markets, aviation, emergency services, and supply-chain coordination.
FAQ
Critical undersea infrastructure includes subsea cables, pipelines, and power connectors that support internet traffic, financial transactions, energy delivery, and secure communications between nations.
It is a NATO-supported structure that coordinates information-sharing, monitoring, and rapid response to CUI threats across the Alliance and partner nations.
NATO provides surveillance coordination, maritime presence, information-sharing frameworks, multi-domain operations, and early-warning mechanisms to help protect allied seabed assets.
Public maps are available through the International Cable Protection Committee (ICPC) and academic institutions that publish seabed cable route charts. Here is an online version that maps some of the underwater infrastructure.
How OCIANA® can help
The protection of critical underwater infrastructure has become a defining issue for global security, economic stability, and digital resilience. NATO’s strengthened engagement – from the Baltic Sea to the Mediterranean – reflects a broader international understanding that seabed networks are essential to modern life yet deeply vulnerable to hybrid threats, natural hazards, and geopolitical competition.
As data capacity grows and states compete for influence beneath the waves, safeguarding underwater infrastructure demands coordinated action across governments, industry, defence alliances, and environmental regulators.
Emerging technologies – including autonomous underwater vehicles, seabed sensor networks, advanced satellite detection, and AI-powered anomaly analysis – offer promising tools to enhance protection efforts.
OCIANA® can support the protection of critical undersea infrastructure by monitoring vessel locations, detecting suspicious vessels that may be concealing their positions or activities, and consolidating sensor information into a single platform for shared awareness, governance, and resilience. Contact us to learn more about why the Government of Canada trusts GSTS’ OCIANA® to support their maritime domain awareness initiatives.
AIS data includes static (ship identity), dynamic (position, speed, course), and voyage-related (destination, ETA) information.
AIS stands for Automatic Identification System.
AIS data can be collected directly through onboard receivers, port-based shore stations, or commercial and satellite AIS providers such as Spire and Marine Traffic.
Yes. Under SOLAS, most commercial vessels and all passenger ships must carry AIS equipment.
Many AIS signals are publicly accessible, though commercial services often aggregate and analyze them to enhance coverage and accuracy.
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