Abstract: The method is that of detecting a network address translation device which transfers network data to a first device. This method includes: obtaining an address of a second device connected to the network; generating pseudo network data in which an address is set as a destination address, and in which a number of times that the network data can be transferred is set as a number of transfers required to reach the first device; transmitting the pseudo network data to the second device; detecting a message from the second device, the message indicating that the pseudo network data cannot be further transferred; and determining that the second device is operating the network address translation device in response to the detection of the message.

Abstract: An apparatus for creating network configuration information from data including packet transmission time between one or more relay devices and a terminal, the relay devices relaying a signal which runs through a network and is measured by the terminal connected to the network, to another network, information about the relay devices and information about the terminal. The apparatus includes systems for: receiving the data from the terminal; arranging the relay devices in the network configuration information based on information about the relay devices; arranging the terminal in the network configuration information based on information about the terminal; arranging packet transmission time between the terminal and the relay devices in the network configuration information; and identifying a subnetwork from the data.

Abstract: The method is that of detecting a network address translation device which transfers network data to a first device. This method includes: obtaining an address of a second device connected to the network; generating pseudo network data in which an address is set as a destination address, and in which a number of times that the network data can be transferred is set as a number of transfers required to reach the first device; transmitting the pseudo network data to the second device; detecting a message from the second device, the message indicating that the pseudo network data cannot be further transferred; and determining that the second device is operating the network address translation device in response to the detection of the message.

Abstract: An apparatus for creating network configuration information from data including packet transmission time between one or more relay devices and a terminal, the relay devices relaying a signal which runs through a network and is measured by the terminal connected to the network, to another network, information about the relay devices and information about the terminal. The apparatus includes systems for: receiving the data from the terminal; arranging the relay devices in the network configuration information based on information about the relay devices; arranging the terminal in the network configuration information based on information about the terminal; arranging packet transmission time between the terminal and the relay devices in the network configuration information; and identifying a subnetwork from the data.