PROBLEM TO BE SOLVED: To provide a network system for making a plurality of devices connected to a network independently display the time change of a feature amount indicating the biological activity of a subject, which is measured by a measuring unit such as an electrocardiograph, while suppressing design loads on the measuring unit.SOLUTION: The measuring unit continuously transmits measurement data to all of the plurality of devices during a period of receiving a transmission request from at least one of the plurality of devices. While the measuring unit is often design to transmit the measurement data to a single device and is not good at complicated control of switching start/stop of transmission of the measurement at independent timing for each of the plurality of devices, in the manner, the measurement data is transmitted to the device requesting the transmission by return without such complicated control.
