In a measurement system that comprises plural measurement devices classified by groups, and plural data processing devices on a network that receives and processes measured data from the measurement devices, the data processing devices are smoothly allocated. The measurement devices belong to groups based on the areas in which they are located, and respectively transmit measured data to a multicast address defined for each of the groups to which they belong. A management device detects an overloaded or failed data processing device, stops data processing on a multicast address at which the data processing device receives data, alternatively commands another less loaded data processing device to join the multicast group, receive measured data transmitted to the multicast address, and process the data.