Abstract: A gateway device (10) relays communication of safety data between a safety input/output unit (40) and a safety controller (20) that controls the safety input/output unit (40), and includes a state monitoring control section (130) and a safety control section (120). The state monitoring control section (130) manages a control state that is a state corresponding to a state of the safety control system (80) and is one of a safety state and a non-safety state, and controls a state transition of the control state by applying safety data that the gateway device (10) has received from the safety input/output unit (40) to state transition information that indicates a state transition concerning the control state. When the control state has transitioned from the non-safety state to the safety state, the safety control section (120) generates safety data that indicates the safety state and is to be transmitted to the safety input/output unit (40).

Abstract: A safety communication device includes: a safety layer parameter acquisition part to acquire a reception bit rate of safety layer data being received per unit time; a threshold value setting part to set a request error rate requested as an upper limit of a bit error rate of the safety layer data received per unit time, on the basis of a request value corresponding to a bit error rate request being requested as an upper limit of an error occurrence probability per bit during data communication in a non-safety network, and a reception bit rate; and a safety monitoring control part to compare the bit error rate of the safety layer data received within a unit time, with the request error rate, and to perform safety control on the basis of a comparison result.

Abstract: A network construction support system (100) generates one or more pieces of layout data (101) indicating a layout of construction assisting tools (140). The network construction support system calculates a countermeasure cost and an estimated risk amount, for each layout data, the countermeasure cost increasing as a number of units of construction assisting tools increases, the estimated risk amount decreasing as the number of units of construction assisting tools increases and as a narrowed range by each construction assisting tool narrows. The network construction support system judges an appropriateness of the layout data for the apparatus network system, for each layout data, on the basis of a countermeasure cost, an estimated risk amount, and an allowable risk amount which is allowed for the apparatus network system, The network construction support system outputs layout data judged to be appropriate for the apparatus network system.

Abstract: A checksum negotiation unit selects as a candidate polynomial, a candidate for a generator polynomial to be used in communication between a safety master device and a safety slave device from a plurality of polynomials. A communication cycle verification unit determines whether or not a calculation using the candidate polynomial is completed in each of the safety master device and the safety slave device by a predetermined deadline. The communication cycle verification unit designates the candidate polynomial as the generator polynomial when it is determined that the calculation using the candidate polynomial is completed in each of the safety master device and the safety slave device by the deadline.

Abstract: A safety communication device includes: a safety layer parameter acquisition part (125) to acquire a reception bit rate of safety layer data being received per unit time; a threshold value setting part (127) to set a request error rate requested as an upper limit of a bit error rate of the safety layer data received per unit time, on the basis of a request value corresponding to a bit error rate request being requested as an upper limit of an error occurrence probability per bit during data communication in a non-safety network, and a reception bit rate; and a safety monitoring control part (124) to compare the bit error rate of the safety layer data received within a unit time, with the request error rate, and to perform safety control on the basis of a comparison result.

Abstract: A checksum negotiation unit (10005) selects as a candidate polynomial, a candidate for a generator polynomial to be used in communication between a safety master device (10) and a safety slave device (20) from a plurality of polynomials. A communication cycle verification unit (10008) determines whether or not a calculation using the candidate polynomial is completed in each of the safety master device (10) and the safety slave device (20) by a predetermined deadline. The communication cycle verification unit (10008) designates the candidate polynomial as the generator polynomial when it is determined that the calculation using the candidate polynomial is completed in each of the safety master device (10) and the safety slave device (20) by the deadline.

Abstract: A region specifying unit specifies a first region where a regular bit string is in a transmission frame, a second region which has a bit string similar to a defined bit string, and a third region which has a non-regular bit string and extracts a difference between the bit string in the second region and the defined bit string. A first CRC acquisition unit acquires a first CRC corresponding to the regular bit string. A second CRC acquisition unit acquires a second CRC corresponding to the defined bit string. A differential CRC acquisition unit acquires a differential CRC corresponding to the extracted difference. A third CRC generation unit generates a third CRC corresponding to a bit string in the third region. A frame CRC generation unit generates a CRC of the transmission frame using the first CRC, the second CRC, the differential CRC, and the third CRC.

Abstract: A controller includes: a task execution management table in which task information including information on task priority is registered; a new task acquisition unit that acquires new task information to be added to the task execution management table; a temporary priority setting unit that changes a priority included in the new task information, to a temporary priority to temporarily register the new task information in the task execution management table; and a task execution monitoring unit that monitors an influence of execution of an additional task on execution of an existing task, the additional task being a task corresponding to the temporarily registered new task information.

Abstract: A region specifying unit (1002) specifies a first region where a regular bit string appears in a transmission frame, a second region where a bit string similar to a defined bit string appears, and a third region where a non-regular bit string appears and extracts a difference between a bit string in the second region and the defined bit string. A first CRC acquisition unit (1003) acquires a first CRC corresponding to the regular bit string from a CRC table. A second CRC acquisition unit (1004) acquires a second CRC corresponding to the defined bit string from the CRC table. A differential CRC acquisition unit (1005) acquires a differential CRC corresponding to the extracted difference from the CRC table. A third CRC generation unit (1006) generates a third CRC corresponding to a bit string in the third region. A frame CRC generation unit (1007) generates a CRC of the transmission frame by using the first CRC, the second CRC, the differential CRC, and the third CRC.