A system for communicating between redundant devices balances the desired attributes of a high availability (HA) control system and a safety control system. The system includes concurrent connections as a fault tolerant mechanism for industrial protocol connections at the transport layer. The concurrent connections establish multiple paths for redundancy from a data producer to a data consumer. Concurrent connections increase availability of the HA control and safety instrumented systems. More specifically, concurrent connections and architectural redundancies eliminate a single point of failure within the control system and further reduce safety connection timeouts during fault detection and/or recovery. Concurrent connections may be used to keep a HA system operational or to provide detection of a failure in a safety system. The industrial control network may be configured to function as a HA control system, as a safety control system, or with certain degrees of both HA and safety-related operation.

An industrial controller executes a control program held in non-transitory medium to: (a) open connections for the communication of data on the industrial control network, the connection subject to a timeout; (b) operate in a synchronized state with the second industrial controller to execute a same control program to communicate same control data; (c) operate in an unsynchronized state providing no-operation data to the industrial control network, the no-operation data preventing timeout of the open connections on which it is communicated.

A packet forwarding circuit (18), such as a programmable switch or router, for example, is disposed between a control server (14) and one or more actuators (17) associated with a robotic arm (16), for example. The packet forwarding circuit is configured to perform real-time velocity control of the one or more actuators in addition to other functionalities that it normally performs, such as routing, packet forwarding, and firewall protection.

An industrial controller executes a control program held in non-transitory medium to: (a) open connections for the communication of data on the industrial control network, the connection subject to a timeout; (b) operate in a synchronized state with the second industrial controller to execute a same control program to communicate same control data; (c) operate in an unsynchronized state providing no-operation data to the industrial control network, the no-operation data preventing timeout of the open connections on which it is communicated.

A system for communicating between redundant devices balances the desired attributes of a high availability (HA) control system and a safety control system. The system includes concurrent connections as a fault tolerant mechanism for industrial protocol connections at the transport layer. The concurrent connections establish multiple paths for redundancy from a data producer to a data consumer. Concurrent connections increase availability of the HA control and safety instrumented systems. More specifically, concurrent connections and architectural redundancies eliminate a single point of failure within the control system and further reduce safety connection timeouts during fault detection and/or recovery. Concurrent connections may be used to keep a HA system operational or to provide detection of a failure in a safety system. The industrial control network may be configured to function as a HA control system, as a safety control system, or with certain degrees of both HA and safety-related operation.