Subsea bandwidth

Subsea bandwidth is the web of undersea fiber-optic cables that carries almost all internet traffic between continents. It matters because the things AI now does across regions — serving inference near users, replicating data, standing up sovereign clouds — all ride a physical layer that is surprisingly thin and painfully slow to repair. What moved it from telecom trivia to strategic surface is the collision of distributed inference with a run of high-profile cable-cut incidents in the Red Sea, the Baltic and around Taiwan.

If this layer tightens, the failure mode is regional and stubborn: multiple cuts in one corridor can degrade intercontinental capacity for weeks, because the scarcest asset is the small fleet of specialized repair ships, and so-called redundant routes often share the same landing funnels. Exposure runs through the cable makers and layers — SubCom, Nokia, NEC and Hengtong — plus the fiber and optical suppliers beneath them, Corning and Ciena.