A process detects anomalies on a controller area network (CAN) bus. An arbitration field in a message on the CAN bus is analyzed, and a data field in the message on the CAN bus is inspected. The process further monitors a frequency of message identifiers that are transmitted across the CAN bus, and determines that an overall bus load crosses a threshold. The process then transmits an alert when the analyzing the arbitration field, the inspecting the data field, the monitoring the frequency, and the determining the overall bus load indicate that an anomaly has occurred on the CAN bus.

A frame transmission prevention apparatus connected to a network of a network system including a plurality of electronic control units communicating with one another via the network is provided. The apparatus includes a processor and a memory. The memory includes at least one set of instructions that causes the processor to perform processes when executed by the processor. The processes include receiving a first frame from the network and switching whether to perform a first process for preventing transmission of the first frame on the basis of management information indicating whether prevention of transmission of a frame is permitted if the first frame satisfies a first condition.

A communication device that can prevent the transmission of a message from being continuously hindered over a long period of time, a communication system and a message arbitration method are provided. The communication device transmits and receives a message to and from another device connected to a common communication line which comprises a calculation unit that calculates as to a message to be transmitted a margin time before a time when a transmission of the message is completed; a transmission unit that transmits the message to which information related to the margin time calculated by the calculation unit is attached; and an arbitration unit that performs arbitration based on the information attached to the message when simultaneous message transmissions to the communication line occur, and as to multiple of messages simultaneously transmitted to the communication line, the arbitration unit performs arbitration in such a manner as to prioritize a message with a shorter margin time.

A method for monitoring data communications in a communications system, which includes a plurality of subscribers and a communications medium jointly usable by the subscribers. The method includes the following steps: ascertaining the subscribers of the communications system; forming a first collection of possible messages, which may be sent by at least one of the ascertained subscribers via the communications medium; and ascertaining messages transmitted via the communications medium; evaluating the ascertained messages.

A transmitting/receiving device for a bus system and a method for reducing an oscillation tendency in the case of coupled-in interferences, in particular, in the transition between different bus states. The transmitting/receiving device has a transmitting stage for transmitting a transmit signal to a first bus wire of a bus of the bus system, and for transmitting the transmit signal to a second bus wire of the bus, and an oscillation reduction module for damping an oscillation of a bus signal arising at terminals for the bus wires when the transmitting/receiving device acts as the transmitter of the transmit signal. The oscillation reduction module includes a first resistor, which is switchable between the first bus wire and a terminal for ground, and the oscillation reduction module including a second resistor, which is switchable between the second bus wire and a terminal for a voltage supply of the bus system.

An in-vehicle relay device for a vehicle is provided. The in-vehicle relay device includes a first communication circuit that transmits and receives first data to and from a first in-vehicle equipment in the vehicle. A second communication circuit transmits and receives second data to and from a second in-vehicle equipment in the vehicle. A control circuit controls relay of third data among the first communication circuit and the second communication circuit. In a case where reception data received by the control circuit from the first communication circuit or the second communication circuit is unauthorized, the control circuit stops relaying the third data in accordance with a traveling state of the vehicle.

An apparatus includes a connector for coupling a cable comprising at least one optical fiber and at least one electrical wire to an optical module at a network communications device, the connector comprising an electrical contact plate for engagement with an electrical contact on the optical module, and a ferrule for receiving the at least one optical fiber. The electrical contact plate is configured for electrically coupling the at least one electrical wire to the electrical contact on the optical module for delivery of power through the optical module.

A bus system, a method for operating a bus system and a participant of a bus system are provided. The participant includes a timer and a transceiver circuit. The transceiver circuit is configured to receive a data packet having a time stamp value via a bus. The timer is configured for synchronization, based on the time stamp value. The timer is configured to change the time stamp value. The transceiver circuit is configured to transmit the data packet with the changed time stamp value via the bus.

A design method for a vehicle control system includes constructing a daisy chain trunk network by a central processing unit and a plurality of zone ECUs, calculating a first activation time from when a network is sequentially activated from a predetermined zone ECU to when the central processing unit is activated, calculating a second activation time from when a network is sequentially activated from the central processing unit to when the zone ECU is activated, and determining a connection destination of an information acquisition unit and a connection destination of an in-vehicle device from the zone ECUs in a manner that a total time of the first activation time and the second activation time is less than a predetermined delay time.

A network includes a plurality of nodes and a plurality of links communicatively coupling each of the nodes to at least one respective adjacent node via a first communication channel and to another respective adjacent node via a second communication channel. The nodes and links have a braided ring topology. First and second nodes of the plurality of nodes source data, are adjacent nodes, and at least one is a source node. The first node sends a first communication to the second node via a third node that is adjacent the first node and via a fourth node that is adjacent the second node. The second node sends a second communication to the first node via the third node and via the fourth node. At least one of the first and second nodes terminates transmission of the first and second communications when the first and second communications do not match.