A submarine interconnector is an undersea power cable system that links electricity networks across borders or regions. It moves electricity between separate grids, often to improve resilience, balance demand, or connect an island system to a larger network.
In cyber security, these projects matter because the cable itself is only one part of the system. The main exposure is usually at landing stations, converter stations, and operational technology used for monitoring, switching, and remote control. Those endpoints can be targeted through weak credentials, unsafe remote access, poor network segmentation, or supply-chain compromise. A successful intrusion may not need to damage the seabed cable; disrupting control systems or communication links can still affect power flow and recovery. Defenders protect interconnectors with strict identity controls, segmented OT networks, logging, tested backups, and coordinated physical and cyber security at both ends of the link.