Researchers have discovered a way to dramatically improve the reliability of high-speed internet. Fiber optic lines use light waves to transfer data, but sending high-speed long-distance communications requires a lot of power. The more power used to transmit a signal, the more interference, or noise, creeps in. A well-established way of dealing with the interference is by inverting the noise to its phase conjugate. As BBC News notes, the concept is similar to how active noise-canceling headphones work.
Noise-canceling headphones monitor the nearby environment with a microphone and generate the inverse signal of what they hear, preventing the noise from being audible. While it's a simple enough concept, there hasn't been an equally-simple way to put it to use in networking. Adding devices to the internet's infrastructure that would detect and filter out noise in this manner has been proposed, but with an enormous number of potential paths for data, it would be expensive and highly impractical to set up.
With mirrored signals, errors cancel themselves out
What lead researcher Xiang Liu and his associates decided to do was send the original data along with its phase conjugate. Sending both a regular and inverted signal makes filtering out noise easy — interference in one wave is mirrored by the other, canceling each other out. This allows for faster data speeds and longer-distance communications. Using twin signals, the team managed to reliably send data at 400Gbps — for context, Google's superfast fiber broadband operates at 1Gbps — over a distance of 12,800 kilometers (just under 8,000 miles). With a lower number of errors, the system would also free up bandwidth by reducing the need to resend data.