Subsea Cables & Internet Infrastructure

Long haul fibre optic bandwidth ranges from a few terabits per second into the low thirties with the equipment and operating expense sharply rising as transmission rates go up. Repeatered subsea cables generally lie in the 12 to 25 Tbps window with most spatial division multiplexing deployments pushing 12 to 20 Tbps whereas the traditional 6 to 8 pair coherent optics deployments transmit at least 20 Tbps or higher per strand.  The key factor determining the optical transmission rate is attenuation, which refers to the fact that a photon or wavelength's intensity or energy diminishes as it travels through fibre optic glass or any other medium. Light is scattered, reflected backwards or absorbed. Other variables that affect transmission rates include the number of distinct wavelength bands (dense wave division multiplexing) that can serve as distinct optical channels in a given spectrum range (usually the C band). The more channels, the higher the transmission rate. Chromatic dispers...