What Are Submarine Cables

🌊 What Are Submarine Cables?

• Definition: Submarine communications cables are fiber‑optic cables placed on the ocean floor to transmit telecommunication signals between continents and countries.
• Function: They connect land‑based stations across oceans, enabling internet, phone, and data services worldwide.
• Importance: Despite satellites, submarine cables handle the overwhelming majority of global data because they are faster, cheaper, and more reliable.

📜 History

• 1850s: First submarine cables carried telegraph signals across the English Channel.
• 1858: First transatlantic telegraph cable became operational, linking Europe and North America.
• 20th century: Transition from telegraph to telephone cables.
• 1980s onward: Fiber‑optic technology revolutionized capacity, enabling modern internet traffic.

⚙️ Structure of Modern Submarine Cables

A typical cross‑section includes:

• Polyethylene outer layer (protection).
• Steel wires (strength).
• Aluminum water barrier.
• Copper or aluminum tube (power conductor).
• Petroleum jelly (insulation).
• Optical fibers (data transmission).

🚢 Deployment

• Laid by specialized cable‑laying ships.
• Routes carefully planned to avoid hazards (earthquakes, fishing zones, shipping lanes).
• Shore ends are buried to protect against damage.

🌍 Global Scale

• Over 400 submarine cables are currently in service worldwide.
• Total length exceeds 1.3 million kilometers.
• They connect virtually every continent, except Antarctica.
• Example: The SEA‑ME‑WE 6 cable links Southeast Asia, the Middle East, and Western Europe.