NETWORK SYSTEM, CONTROLLER, AND CONTROL METHOD

PROBLEM TO BE SOLVED: To provide a network system, a controller, and a control method capable of controlling the colors of light emitted by an illumination favorably according to the location.SOLUTION: A network system 1 includes a plurality of temperature sensors 120A to 120D, a plurality of illuminations 130A to 130D for illuminating the respective peripheries of the plural temperature sensors, and a controller 100 which, when the temperature from any of the plural temperature sensors is high, controls the illumination corresponding to that temperature sensor so as to emit a cold color based light and, when the temperature from any of the plural temperature sensors is low, controls the illumination corresponding to that temperature sensor so as to emit a warm color based light.