But, if light bounces in every obstacle, it will be confined to just a room or so... Then, I think is unreliable for the general public and will be only useful in specific situations... Which I can't think of a single one... Not getting interference with Military, Hospitals and Airplanes isn't already achieved by separating special frequencies for WiFi and Bluetooth? How that is achieved today?
And not only each individual room, but do physical objects block the light transmission? So just simply moving around a room will constantly interrupt the connection?