Understanding the Role of Submarine Cable Networks

Submarine cable networks are essential to the global digital economy, acting as the backbone of internet connectivity. They carry massive data volumes — nearly 6,400 Terabits/second (Tbps) — and are constantly growing in capacity. However, they face risks from geopolitical tensions, natural disasters, and deliberate sabotage, making their protection critical.

What Are Subsea Cables?

• Subsea cables are fiber-optic cables laid on the seabed to transmit internet and telecommunication data.
• They connect continents and countries, ensuring global communication.
• India currently connects through 18 cable systems, with more in development.

Why Are They Important?

• Enable global internet connectivity, cloud services, and data transfer.
• Vital for international trade, finance, defence communication, and everyday internet use.
• Around 500,000 km of new cables are being laid annually to meet growing data demands.

Risks and Vulnerabilities

1. Cable Faults
   Caused by fishing activities, shipping anchors, and natural disasters.
   Average repair time: 17 days (e.g., India-Singapore cable fault).
   Sabotage & Geopolitical Risks: Taiwan and Europe have reported deliberate cable cutting. Vulnerabilities increase during conflicts, as seen in the Ukraine war.
   High Repair Costs: Specialized ships and crews are required, costing $30–100 million annually. India is a growing hub for data traffic in Asia, heavily reliant on international subsea networks.
2. Most of India’s connectivity routes pass through Singapore, creating dependency risks.
3. Need for Alternative Routes and Domestic Cable Landing Stations:
   • Cable Connectivity and Resilience Centre set up by the Department of Economic Affairs.
   • Collaborative repair facilities shared by governments and carriers.
   • Adoption of Cable Protection Zones and Automated Underwater Vehicles (AUVs) for monitoring.
   • Legal penalties under the Telecommunications Act for intentional damage.
4. Subsea cables form the hidden backbone of the internet, carrying 99% of global data traffic. India’s digital economy depends on them, yet they are vulnerable to natural, accidental, and deliberate disruptions. With growing dependence on digital infrastructure, India must invest in protection mechanisms, diversify routes, and strengthen repair capacity to ensure uninterrupted internet services and strategic security.

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   Power and communication lines beneath the sea are the silent lifelines of nations, and protecting them is protecting sovereignty.