Fiber cables made of air move data at 99.7 percent the speed of light

Researchers say they have created fiber cables that can move data at 99.7 percent of the speed of light, all but eliminating the latency plaguing standard fiber technology. There are still data loss problems to be overcome before the cables could be used over long distances, but the research may be an important step toward incredibly low-latency data transmissions.

Although optic fibers transmit information using beams of light, that information doesn't actually go at "light speed." The speed of light, about 300,000 km/s, is the speed light travels in a vacuum. In a medium such as glass, it goes about 30 percent slower, a mere 200,000 km/s.

"[L]ight propagates 31% slower in a silica glass fibre than in vacuum, thus compromising latency," notes a paper published Sunday in Nature Photonics, titled "Towards high-capacity fibre-optic communications at the speed of light in vacuum."