PROBLEM TO BE SOLVED: To provide means for realizing reduction of power consumption or communication fee in a system comprising: measurement devices arranged in raising fields of animals and plants a server device which uses data showing measurement results of measurement devices and relay devices which relay data communication from the measurement devices to the server device.SOLUTION: Measurement devices 11 installed in raising fields FD of animals and plants measure an environmental attribute, and transmit data showing measurement results to relay devices 12. The relay devices 12 transmit data received from the measurement devices 11 to a server device 13. The server device 13 transmits data showing transmission interval of data to the relay devices 12 such that a transmission frequency of data from the measurement devices 11 to the relay devices 12 and a transmission frequency of data from the relay devices 12 to the server device 13 become appropriate frequency based on the environmental attribute measured in the raising fields FD and appropriate values of environmental attribute corresponding to types of animals and plants raised in the raising fields FD.SELECTED DRAWING: Figure 1
