“Every 1 meter of fiber, more or less, we can turn it into a kind of microphone,” says Ozharar.
NEC Laboratories was using a fiber test bed in Princeton to listen for seismic activity and picked up Brood X instead. Distributed acoustic sensing fires a laser down the cable and reads the light that bounces back. A buried line already detects people walking and driving above it. Entomologists see a cheap insect census. Everyone else should see that every fiber run under a city is a microphone.