The most powerful electromagnetic spectrum can be achieved using light or signal. This is achieved by means of LASER.

Laser always travel on the  straight line.Hence the line of sight is required in it. Because laser transmission is unidirectional type so installation at both the end laser and photo detector is not required for receiving or transmitting data.

Laser beam is generally 1mm wide hence it is a work of precision to align two far receptors each pointing to lasers source.

Laser works as Tx (transmitter) and photo-detectors works as Rx (receiver).

Lasers cannot penetrate obstacles such as walls, rain, and thick fog. Additionally, laser beam is distorted by wind, atmosphere temperature, or variation in temperature in the path.

Laser is safe for data transmission as it is very difficult to tap 1mm wide laser without interrupting the communication channel.