Japan’s new internet speed could download the MCU in the time it takes to blink

In a significant advancement for global communication technology, researchers from Japan's National Institute of Information and Communications Technology (NICT), in collaboration with Sumitomo Electric Industries, have achieved the fastest long-distance optical data transmission ever recorded. The team successfully transmitted data at an astonishing rate of 1.02 petabits per second over a distance of 1,808 kilometers, utilizing a specially engineered 19-core optical fiber. To put this achievement into perspective, the distance covered is comparable to traveling from Sapporo to Fukuoka in Japan, from Missouri to Montana in the United States, or from Berlin to Naples in Europe. Remarkably, the volume of data transmitted in just one second exceeds the total daily internet usage of all users worldwide. This groundbreaking discovery was unveiled at the 48th Optical Fiber Communication Conference (OFC 2025) in April, marking a new world record for both speed and distance in optical fiber communications. The capacity-distance product achieved was an unprecedented 1.86 exabits per second-kilometer, the highest recorded to date. What adds to the significance of this breakthrough is that the 19-core fiber has the same outer diameter (0.125 mm) as standard single-core optical fibers, allowing it to be compatible with existing network infrastructure, which could facilitate its practical implementation. Previous attempts had succeeded in surpassing 1 petabit per second, but those were restricted to much shorter distances. The innovative design of the low-loss, wide-bandwidth 19-core fiber enables data signals to travel longer distances without degradation in quality. Sumitomo Electric manufactured the fiber, ensuring minimal signal losses across the commonly utilized C and L wavelength bands. NICT and its collaborators developed an advanced system capable of sending and receiving signals simultaneously through all 19 cores. This elaborate setup included a transmitter, a receiver, and 19 recirculating loops, each spanning 86.1 kilometers. The data traversed these loops 21 times, culminating in a total transmission distance of 1,808 kilometers. To preserve signal integrity, the system employed optical amplifiers—two per core, one for each wavelength band—together utilizing 180 wavelengths, with each carrying data formatted in a high-capacity method known as 16QAM (Quadrature Amplitude Modulation). As demand for data continues to surge due to the rise of services like video streaming, cloud computing, and 5G technology, such breakthroughs become increasingly vital. The success of this project indicates that multi-core fibers, which allow the simultaneous transmission of multiple light signals, could be essential in developing future high-capacity internet systems. Previously, long-distance high-speed transmissions were hindered by either the number of cores or signal loss over extensive distances. However, this new advancement demonstrates that with optimal design and amplification systems, scalable and long-range high-speed networks are within reach. This research is part of a broader initiative by NICT and global researchers aimed at exploring new fiber types, including multi-mode and coupled-core fibers, to push beyond current technological limitations. While earlier experiments with these fiber types showed potential, they were often constrained by complex signal processing challenges. This latest success with coupled-core 19-core fiber over long distances marks a significant step forward in the quest for faster, more efficient data transmission. This record-breaking achievement is not just a technical milestone; it heralds a future where data can travel faster, farther, and more efficiently, paving the way for advancements in communication technology.