Submarine cable
termISP & telecomnetworking
The fibre-optic cable laid on the seabed that carries essentially all intercontinental internet traffic - fibre pairs at the core, wrapped in steel and copper, roughly garden-hose thick in deep water and heavily armoured near shore.
Most faults are accidental, caused by fishing gear and anchors in shallow water, and most are invisible to users because traffic reroutes. The dangerous property is correlation: geography forces cables into shared corridors and shared landing areas, so systems bought as independent frequently are not. When assessing resilience the question is never how many cables a country has, but how many physically separate paths, landing points and terrestrial backhauls stand behind them.
Also known as: subsea cable, undersea cable, cabo submarino, fibre pair