Abstract: A method and network access point selection logic are described for a redundantly connected industrial LAN node including at least primary and backup network access points. Network connectivity is determined by a redundantly connected node by testing connectivity between the node's primary and backup physical network access points. Upon detecting a loss of connectivity between the redundant node's primary and backup network access points, the node executes access point selection logic, based upon tests of connectivity between the redundantly connected (primary and backup) network access points and a set of nodes on the LAN, to select a preferred/primary one of the redundant access points. Thereafter, the redundantly connected node binds its connections according to primary and backup designations for its redundant network access points.

Abstract: Schemes for synchronizing networked stations using data messages and hardware pulses are described herein. In one embodiment, a method to provide time data from a first processor to at least one second processor may include transmitting a data message from the first processor to the at least one second processor, in which the data message associates a hardware pulse with a future time, and transmitting a hardware pulse from the first processor to the at least one second processor at the future time.

Abstract: A fault router method and system for use in a parallel redundant network environment provide additional safeguards over traditional redundant networks. Where multiple connection faults on multiple machines would ordinarily stifle communications between two or more network entities, the fault router passes packets between redundant networks to bypass connection faults. Compatibility and timing improvements allow for the extension of the parallel network environment, and provide for time-synchronized network operation.

Abstract: A fault router method and system for use in a parallel redundant network environment provide additional safeguards over traditional redundant networks. Where multiple connection faults on multiple machines would ordinarily stifle communications between two or more network entities, the fault router passes packets between redundant networks to bypass connection faults. Compatibility and timing improvements allow for the extension of the parallel network environment, and provide for time-synchronized network operation.

Abstract: A fault router method and system for use in a parallel redundant network environment provide additional safeguards over traditional redundant networks. Where multiple connection faults on multiple machines would ordinarily stifle communications between two or more network entities, the fault router passes packets between redundant networks to bypass connection faults. Compatibility and timing improvements allow for the extension of the parallel network environment, and provide for time-synchronized network operation.

Abstract: A control system has a first module that includes a memory and diagnostic logic. The diagnostic logic periodically tests at least selected locations in the memory and, in connection with such testing, reads data from those locations and writes that data back to the locations. A second module is coupled to the first module such that the written back data is transferred to the second module, as well as to the memory of the first. Mapping or other conversion logic can translate addresses or other data identifiers, as necessary, to insure that the transferred data is properly identified upon its receipt by the second module.

Abstract: Schemes for synchronizing networked stations using data messages and hardware pulses are described herein. In one embodiment, a method to provide time data from a first processor to at least one second processor may include transmitting a data message from the first processor to the at least one second processor, in which the data message associates a hardware pulse with a future time, and transmitting a hardware pulse from the first processor to the at least one second processor at the future time.

Abstract: A fault router method and system for use in a parallel redundant network environment provide additional safeguards over traditional redundant networks. Where multiple connection faults on multiple machines would ordinarily stifle communications between two or more network entities, the fault router passes packets between redundant networks to bypass connection faults. Compatibility and timing improvements allow for the extension of the parallel network environment, and provide for time-synchronized network operation.

Abstract: A computer is connected to redundant network switches by primary and secondary connections, respectively. Test messages are sent across each connection to the attached switches. A break in a connection, or a faulty connection, is detected upon a failed response to one of the test messages. In response to this failure, traffic is routed across the remaining good connection. To facilitate fast protocol rerouting, a test message is sent across the now active connection bound for the switch connected to the failed connection. This message therefor traverses both switches causing each to learn the new routing. Rerouting is therefor accomplished quickly.