The cable infrastructure enabling South Africa’s access to the Internet has undergone significant improvements over the past 25 years. Advances in multiplexing and increased capacity have transformed the country’s Internet landscape.

The demand for data has skyrocketed with the rise of media-rich websites, social media, YouTube, and Netflix. This surge in demand has driven innovation in data transmission technology. Recently, researchers achieved transfer speeds of 301 Tbps over a single wavelength using existing fibre optic cables.

Fibre strands use multiple wavelengths to transfer data, and wavelength-division multiplexing (WDM) enables multiple carrier signals to be transmitted over a single optical strand. This technology allows for bidirectional communications over the same strand of fibre.

South Africa’s submarine fibre cables have also undergone significant upgrades. The South Atlantic 3 (SAT-3) cable, initially installed in 2001 with a capacity of 120 Gbps, now has a design capacity of 340 Gbps. Other cables, such as Seacom and EASSy, have also seen substantial capacity upgrades over the years.

Today, South Africa’s Internet infrastructure boasts capacities exceeding 400 Tbps, a remarkable achievement in the country’s Internet revolution.