Japan sets new internet speed record at 402Tbps using standard fibre optics

A team of Japanese researchers has broken the world record for internet speed, achieving a staggering data transmission rate of 402 terabits per second (Tbps), or 4,02,000,000 megabits per second (Mbps).

The breakthrough, led by scientists from Japan's National Institute of Information and Communications Technology (NICT), significantly surpasses the previous record of 321 Tbps set in 2023, according to a media statement released on their website.

To illustrate the magnitude of the achievement: at 402 Tbps, downloading a game the size of Elden Ring — over 18 Giga Bites — would take less than a millisecond.

More remarkably, the research was conducted using standard, commercially available fibre optic cables.

According to NICT, the team succeeded in transmitting 37.6 THz (terahertz) of bandwidth across 50 kilometres of fibre. The development utilised the world's first O to U-band transmission system capable of dense wavelength division multiplexing (DWDM) in standard optical fibre.

This was made possible through custom-designed amplifier technology, including a combination of six doped-fibre amplifier variants with lumped and distributed Raman amplification.

The innovation demonstrates how existing infrastructure can be pushed far beyond its current commercial limits. While such speeds are far from feasible for home or commercial consumer use currently, NICT claims that the findings provide a glimpse into the future of ultra-high-speed internet infrastructure.

Despite the record-setting result, practical deployment remains distant.

Current consumer hardware — from Ethernet ports to solid-state drives — is incapable of processing data at such rates. Nevertheless, the breakthrough is expected to inform future improvements in data centres, national internet backbones, and undersea cables.

"It is expected that the data-rate of optical transmission systems required to enable 'Beyond 5G' information services will increase enormously. New wavelength regions enable deployed optical fibre networks to perform higher data-rate transmission and extend the useful life of existing network systems," the release said.

"It is also anticipated that new bands can address the increasing demand of next generation communications services by combining with new types of optical fibres," it added.