Abstract: A relay that controls packet transfer includes: a storage that stores output cycle control information in which an output cycle at which a packet identified by identification information is output, and a determination value indicating whether to output the packet identified by the identification information are set for a set of a port as an output destination of the packet and the identification information for identifying the packet; a cycle controller that rewrites the determination value at each set output cycle; and a transfer processor that controls output of the received packet, in accordance with the determination value.

Abstract: A communication apparatus that forms, in a train in which fixed formations are coupled, a backbone network relaying signals between branch networks formed in the fixed formations with another communication apparatus that is made redundant, includes: a VRRP functional unit that, when operating as a master, periodically transmits an alive monitoring frame to another communication apparatus operating as a backup via the branch network, and, when operating as a backup, receives an alive monitoring frame transmitted from another communication apparatus operating as a master via the branch network; a port-malfunction detection unit detecting malfunction of the port to which the branch network is connected; and an alive determination unit that, when operating as a backup, detects whether another communication apparatus operating as a master has malfunctioned based on an alive-monitoring-frame reception result from the VRRP functional unit and a malfunction detection result from the port-malfunction detection unit.

Abstract: A central device includes an information replacing unit. When the information replacing unit detects, on the basis of contact information acquired from an electric coupler provided in a coupled vehicle in a formation B having a train-information management device that manages vehicle information in accordance with the Ethernet® protocol, that a formation A that includes a train-information management device that manages vehicle information in accordance with the ARCNET protocol is coupled to the formation B, then the information replacing unit replaces vehicle information from the formation A with vehicle information in accordance with the Ethernet® protocol; outputs the replaced vehicle information to the formation B; replaces the vehicle information from the formation B with the vehicle information in accordance with the ARCNET protocol; and outputs the replaced vehicle information to the formation A.

Abstract: A communication apparatus that forms, in a train in which fixed formations are coupled, a backbone network relaying signals between branch networks formed in the fixed formations with another communication apparatus that is made redundant, includes: a VRRP functional unit that, when operating as a master, periodically transmits an alive monitoring frame to another communication apparatus operating as a backup via the branch network, and, when operating as a backup, receives an alive monitoring frame transmitted from another communication apparatus operating as a master via the branch network; a port-malfunction detection unit detecting malfunction of the port to which the branch network is connected; and an alive determination unit that, when operating as a backup, detects whether another communication apparatus operating as a master has malfunctioned based on an alive-monitoring-frame reception result from the VRRP functional unit and a malfunction detection result from the port-malfunction detection unit.

Abstract: A central device includes an information replacing unit. When the information replacing unit detects, on the basis of contact information acquired from an electric coupler provided in a coupled vehicle in a formation B having a train-information management device that manages vehicle information in accordance with the Ethernet® protocol, that a formation A that includes a train-information management device that manages vehicle information in accordance with the ARCNET protocol is coupled to the formation B, then the information replacing unit replaces vehicle information from the formation A with vehicle information in accordance with the Ethernet® protocol; outputs the replaced vehicle information to the formation B; replaces the vehicle information from the formation B with the vehicle information in accordance with the ARCNET protocol; and outputs the replaced vehicle information to the formation A.

Abstract: A second-system terminal device installed in one vehicle is connected to a first-system backbone transmission line and a second-system backbone transmission line, and when having received a status information packet B from a first-system terminal device installed in another vehicle from the first-system backbone transmission line or the second-system backbone transmission line, the second-system terminal device installed in the one vehicle transfers a control packet A to the second-system terminal device adjacent to a side farther from a central device than the second-system terminal device that has received the status information packet B, by using the backbone transmission line from which the status information packet B has been received.

Abstract: Relay devices 1 and vehicle monitoring control devices 2 include communication cycle management sections 111 and 211 for managing communication cycles in accordance with cycle information that divides the communication cycle to communication enabled periods which include a period of enabling only communication of a message to be communicated periodically and correspond to a communication period of a message; and carry out communication in the communication cycles managed by the communication cycle management sections 111 and 211.

Abstract: Relay devices 1 and vehicle monitoring control devices 2 include communication cycle management sections 111 and 211 for managing communication cycles in accordance with cycle information that divides the communication cycle to communication enabled periods which include a period of enabling only communication of a message to be communicated periodically and correspond to a communication period of a message; and carry out communication in the communication cycles managed by the communication cycle management sections 111 and 211.