How Submarines Threaten the Internet: The Vulnerabilities of Undersea Cables
In today’s interconnected world, the vast majority of global internet traffic—over 95%—traverses through an extensive network of undersea fibre-optic cables. These cables, lying on the ocean floor, are the backbone of international communication, enabling everything from financial transactions to video streaming. However, their concealed nature and critical importance make them susceptible to various threats, including deliberate sabotage by state and non-state actors.
The Strategic Importance of Undersea Cables
Submarine cables are indispensable to the global economy and security. They facilitate trillions of dollars in financial transactions daily and support critical infrastructure, including military communications. Despite their significance, however, these cables are vulnerable to damage from natural disasters, accidental human activities, and intentional attacks. While the network’s redundancy often mitigates the impact of unintentional damages, coordinated attacks pose a substantial risk.
Recent Incidents Highlighting Vulnerabilities
In November 2024, two significant undersea cables in the Baltic Sea—the BCS East-West Interlink and C-Lion1—were severed almost simultaneously. These incidents disrupted internet connectivity between several European countries and raised suspicions of deliberate sabotage. Investigations pointed towards potential involvement of state actors, with a Chinese cargo ship, Yi Peng 3, coming under scrutiny for its presence near the damaged cables. While conclusive evidence is yet to be presented, the incidents underscore the geopolitical tensions surrounding undersea infrastructure (source).
Further compounding these concerns, NATO has initiated Operation Baltic Sentry, a mission to patrol and protect vital underwater infrastructure in the Baltic Sea. This operation involves elite divers, submersible drones, and advanced aircraft to safeguard against suspected Russian and Chinese sabotage efforts. The deployment of a 36-foot stealth submarine drone, dubbed “Blue Whale,” exemplifies the advanced measures being taken to monitor and secure these critical assets (source).
The Role of Submarines in Potential Sabotage
Submarines, with their stealth capabilities, are uniquely positioned to access and potentially damage undersea cables. Military strategists have long considered the possibility of using submarines to disrupt communication networks during conflicts. The ability to sever or tap into these cables can provide strategic advantages, such as intelligence gathering or crippling an adversary’s communication infrastructure. The presence of Russian submarines near undersea cables has been a point of concern for NATO allies, prompting increased surveillance and defensive measures (source).
Mitigation and Protective Measures
To address these threats, nations and international organisations are implementing several strategies:
- Enhanced Surveillance: Deploying advanced monitoring systems, including uncrewed underwater vehicles and satellite imagery, to detect suspicious activities near critical cable routes.
- International Cooperation: Collaborating through alliances like NATO to share intelligence and coordinate responses to potential threats.
- Infrastructure Resilience: Investing in the fortification of cable infrastructure, such as burying cables deeper beneath the seabed and developing rapid repair capabilities.
- Legal Frameworks: Establishing and enforcing international laws that protect undersea cables from malicious activities, ensuring that perpetrators are held accountable.
Conclusion
The incidents in the Baltic Sea serve as a stark reminder of the vulnerabilities inherent in the global communication infrastructure. As geopolitical tensions persist, protecting undersea cables becomes paramount. Nations must proactively enhance the security and resilience of these critical lifelines to safeguard the uninterrupted flow of information worldwide.
