Abstract: A node transmits data based on a routing information table when receiving the data. The node determines whether a second candidate neighboring node of which flag information is true and to which the data has not yet been transmitted is present when the data transmission to a first candidate neighboring node fails. The node aborts retransmission of the data when no second candidate neighboring node of which the flag information is true and to which the data has not yet been transmitted is present.

Abstract: A network relay node device for relaying communication between a first network and a second network having a protocol different from a protocol of the first network through a switch, the network relay node device includes an identical segment information generation control unit that generates identical segment information for identification of another relay node device belonging to a same segment as a local device in the second network and a loop suppression control unit that suppresses a loop of a communication including the switch by broadcasting a received broadcast frame only to a connection port of the first network if the identical segment information is detected in identification source node information acquired from a header of the broadcast frame when the broadcast frame is received from a connection port of the first network.

Abstract: A node apparatus includes a receiving unit receiving a data frame from one of adjacent nodes apparatuses; a storing unit storing an identification information management table in which frame identification information with which the data frame may be uniquely identified, and overlapped data identification information; a processor which performs a process including: judging whether or not a final destination of the received data frame is the node apparatus itself; judging whether or not a registration that matches the frame identification information of the received data frame exists in the identification information management table; judging whether or not the overlapped data identification information of the received data frame and the overlapped data identification information corresponding to the registration match; and discarding the received data frame; and performing a retransmission of the received data frame to another adjacent node that has not been a transmission destination of the data frame.

Abstract: A node apparatus includes a receiving unit receiving a data frame from one of adjacent nodes apparatuses; a storing unit storing an identification information management table in which frame identification information with which the data frame may be uniquely identified, and overlapped data identification information; a processor which performs a process including: judging whether or not a final destination of the received data frame is the node apparatus itself; judging whether or not a registration that matches the frame identification information of the received data frame exists in the identification information management table; judging whether or not the overlapped data identification information of the received data frame and the overlapped data identification information corresponding to the registration match; and discarding the received data frame; and performing a retransmission of the received data frame to another adjacent node that has not been a transmission destination of the data frame.

Abstract: Anode device includes a transmitter and a processor. The transmitter transmits an inspection frame used in inspecting a status of a route from a source node device to a destination node device. The processor generates a first inspection frame and selects a first node device to which the transmitter transmits the first inspection frame from among candidates for a node device to which a frame addressed to the destination node device is to be forwarded. The processor judges whether a transmission of the first inspection frame has been successfully performed. When the transmission of the first inspection frame has failed, the processor generates a second inspection frame which records a failure in a communication with the first node device. The processor selects a second node device to which the transmitter transmits the second inspection frame from among the candidates.

Abstract: Anode device includes a transmitter and a processor. The transmitter transmits an inspection frame used in inspecting a status of a route from a source node device to a destination node device. The processor generates a first inspection frame and selects a first node device to which the transmitter transmits the first inspection frame from among candidates for a node device to which a frame addressed to the destination node device is to be forwarded. The processor judges whether a transmission of the first inspection frame has been successfully performed. When the transmission of the first inspection frame has failed, the processor generates a second inspection frame which records a failure in a communication with the first node device. The processor selects a second node device to which the transmitter transmits the second inspection frame from among the candidates.

Abstract: A node transmits data based on a routing information table when receiving the data. The node determines whether a second candidate neighboring node of which flag information is true and to which the data has not yet been transmitted is present when the data transmission to a first candidate neighboring node fails. The node aborts retransmission of the data when no second candidate neighboring node of which the flag information is true and to which the data has not yet been transmitted is present.

Abstract: A first node device transmits a first path information frame including first path information that associates a destination node device with a first forwarding destination to which the first node device forwards a data frame destined for the destination node device. A second node device other than the first node device receives the first path information frame. The second node device determines whether a forwarding path includes a loop. The forwarding path is a path from the second node device to the destination node device via the first node device and the first forwarding destination. The second node device stores the first path information upon determining that the forwarding path does not include a loop. The second node device forwards a data frame destined for the destination node device to the first node device on the basis of the first path information.

Abstract: A data signal transmission control apparatus includes a connection unit for connecting a plurality of first lines and any one of at least one second line that are accommodated in a switching unit between the first lines and the second lines for transmitting a speech signal; a control unit for controlling the connection operation of the connection unit; and an isolation/insertion unit for isolating a data signal, flowing on one of the first and second lines connected by the connection unit, from the one line and inserting the data signal isolated from the one line onto the other line.