Network monitoring system and network monitoring method

There are provided a network monitoring system and a network monitoring method which are capable of obtaining results of monitoring devices on a network with accuracy. Monitor probe servers are provided in respective different layers of a network to determine operating states of devices on the network. A monitor server monitors the operating states of the devices on the network, based on the output from the monitor probe servers. The monitor probe servers transmit monitoring commands to the devices on the network, receives responses to the commands from the devices, and outputs the received responses to the monitor server, which in turn analyzes the responses received from the monitor probe servers, and displays results of the analysis.