Every time you send an email, stream a Netflix show, make a UPI payment, or execute a stock trade, that data isn’t bouncing off satellites it’s traveling through undersea cables, buried under thousands of meters of ocean. These submarine fiber-optic cables form the invisible backbone of the global internet, carrying 95–99% of international data traffic. With over 600 active cables spanning 1.3 million kilometres, they connect continents, support cloud services, video streaming, financial markets, and digital payments, making them vital for global connectivity and economic growth.
Critical hubs in the US, Western Europe, and Asia, along with chokepoints like the Red Sea and Strait of Malacca, highlight their strategic importance. Major players like NEC Corporation, SubCom, Alcatel Submarine Networks, and tech giants such as Google, Meta, and Amazon drive this industry. As AI adoption rises, cloud computing scales, and geopolitical tensions grow, undersea cables have become one of the most valuable and vulnerable digital assets. This blog explores what undersea cables are, why they matter, their risks, key companies, and how India’s digital future depends on them.
What are undersea cables?
• Long, insulated cables (often thousands of km) laid across oceans
• Carry data as light signals through fiber optics
• Connect landing stations in different countries
How to read these maps (very important)
1) Thick clusters = economic power
• US East Coast
• Western Europe
• Singapore / India / Japan
- These are data hubs of the world
2) Thin connections = vulnerability
• Africa
• Some parts of South America
- Fewer cables = higher disruption risk
3) Chokepoints = strategic risk
• Egypt (Red Sea)
• South China Sea
• Strait of Malacca
- These areas control global data flow
- Why they are critically important
1) Backbone of global internet
• ~95–99% of international data traffic flows through these cables (not satellites)
• Everything from WhatsApp, emails, cloud, banking, stock markets depends on them
2) Faster and cheaper than satellites
• Much lower latency (important for trading, gaming, video calls)
• Higher bandwidth ? can carry massive data volumes at low cost
3) Critical for financial markets
• High-frequency trading, forex, and global stock exchanges rely on millisecond-level speeds
• Even small delays can impact arbitrage opportunities
4) National security & geopolitics
• Countries monitor and protect cables because:
o Data interception risks
o Vulnerability to sabotage (accidents or intentional damage)
• Control over cable routes = strategic influence
5) Digital economy enabler
• Supports:
o IT/ITES (India’s outsourcing sector)
o Cloud services (AWS, Azure, Google Cloud)
o Streaming (Netflix, YouTube)
• Without cables, globalization of digital services collapses
- Key risks / challenges
- Physical damage
• Fishing nets, ship anchors, earthquakes
• Repairs can take days to weeks
- Geopolitical risks
• Sensitive choke points (e.g., Red Sea, South China Sea)
• Increasing concern over sabotage or surveillance
- Capacity concentration
• Few routes carry huge traffic ? single point of failure risk
- India angle
• India connects globally via landing points in Mumbai, Chennai, Kochi
• Heavily dependent on cables for:
o IT exports
o Digital payments ecosystem (UPI, banking)
• Big tech firms (Google, Meta) are now investing directly in cables
- Simple analogy
Think of undersea cables as “data highways under oceans”
• Satellites = small air routes (slower, expensive)
• Cables = massive expressways (fast, cheap, high capacity)
Disruptions caused if Undersea cables are attacked
Immediate disruptions
1) Internet slowdowns or outages
• Countries dependent on affected routes (like India–Europe via Egypt) see:
o Slower speeds
o Higher latency (lag in calls, trading, apps)
• In extreme cases ? partial internet blackout
2) Cloud & digital service failures
• Services impacted:
o AWS, Azure, Google Cloud
o WhatsApp, Gmail, YouTube, Netflix
• Apps may:
o Load slowly
o Fail intermittently
o Disconnect (especially real-time services
3) Financial market disruption ?
• Stock exchanges & trading systems rely on ultra-low latency
• Impact:
o Delayed order execution
o Arbitrage opportunities vanish or misfire
o Forex & derivatives markets become inefficient
• Worst case: temporary trading halts
- Economic consequences
4) IT & outsourcing sector hit (India-specific)
• India’s IT exports depend heavily on global connectivity
• Disruption
o Delays in project delivery
o SLA penalties
o Client dissatisfaction
5) E-commerce & payments disruption
• UPI, card networks, payment gateways may slow down
• Cross-border payments (SWIFT, fintech) get delayed
6) Aviation & logistics
• Airlines rely on real-time data for:
o Navigation updates
o Ticketing systems
• Shipping & ports also depend on global data links
- Strategic & geopolitical impact
7) National security risks
• Military communications may be affected
• Intelligence data flows disrupted
• Risk of data interception if cables are tapped
8) Panic & misinformation
• Social media disruptions ? information vacuum
• Can trigger:
o Panic selling in markets
o Spread of rumors
Real-world example
• Red Sea cable damage (2024):
o Disrupted ~25% of traffic between Asia–Europe
o India saw latency spikes and rerouting delays
Top Companies in the world who are in the business of undersea Cables
Global leaders (oligopoly)
1. NEC Corporation (Japan)
• One of the top 3 global players
• Has deployed 400,000+ km of submarine cables worldwide
• Strong in Asia–Pacific routes
2. SubCom (USA)
• Major builder of transoceanic cables
• Works with governments, telcos, and hyperscalers
• Historically linked with large global internet backbone projects
3. Alcatel Submarine Networks (ASN) (France)
• Controls ~of global market along with NEC & SubCom
• End-to-end player: manufacturing + laying + maintenance
• Very strong in Africa & Europe routes
- Key insight:
These 3 companies basically form a global oligopoly in building large international cables.
- Other major manufacturers
4. Prysmian Group (Italy)
• World’s largest cable manufacturer overall
• Leader in subsea power cables (offshore wind, grids)
5. Nexans (France)
• Strong in high-voltage submarine power cables
• Key player in renewable energy interconnects
6. Sumitomo Electric (Japan)
• Major supplier of both power + telecom subsea cables
7. Hengtong / HMN Tech (China)
• Fast-growing global challenger
• Strong presence in Asia & Africa projects
2) Big Tech (owners & investors)
These companies don’t manufacture cables but are now the largest investors and partial owners.
- Key players:
• Google
• Meta (Facebook)
• Amazon (AWS)
• Microsoft
- Why they matter:
• They fund ~40% of new cable investments
• Own/lease capacity to run:
o Cloud (AWS, Azure)
o Apps (WhatsApp, YouTube, Instagram)
- Trend:
• Moving from consortium ownership ? private cables (strategic control)
3) Key component & ecosystem players
8. Corning (USA)
• Makes optical fiber used inside cables
• Critical enabler of high-speed transmission
9. Nokia (Finland)
• Provides network equipment & submarine systems
10. NKT (Denmark), ZTT (China)
• Important in power cable systems
India plays (INDIRECT – but important for you)
India doesn’t have a pure submarine cable company, but these benefit:
- Telecom & bandwidth
Bharti Airtel
• Owns global cable assets (via Airtel Global Network)
Tata Communications
• Major global subsea cable network operator
- Benefit from:
• Higher data traffic
• Leasing capacity
- Cable manufacturers (partial exposure)
Apar Industries
• Mentioned in global cable ecosystem
- More into power cables, but indirect tailwind
- Data center theme
• AdaniConneX
• Reliance (Jio + cloud ambitions)
- More cables = more data = more DC demand
Macro tailwinds (why this theme is strong)
• AI + cloud explosion
• Data localization
• Redundancy (avoid Egypt-type chokepoints)
• Geopolitical diversification
- Global investments already rising sharply (multi-billion $ annually)
Undersea cables typically last 25–30 years, but regular maintenance, upgrades, and repairs are required to ensure continuous operation.
Specialized ships locate the damaged section, bring it to the surface, repair or replace the fiber-optic cable, and lay it back on the ocean floor, which can take days to weeks depending on depth and location.
Modern submarine cables can transmit terabits of data per second, supporting global internet traffic, cloud services, video streaming, and financial transactions.
India relies on undersea cables for IT exports, digital payments (UPI), cloud services, and international communications, connecting major hubs like Mumbai, Chennai, and Kochi to the global internet.
Cable installation can temporarily disturb marine ecosystems, but modern techniques aim to minimize environmental impact while ensuring safe deployment.