Real time data communication via OPC UA
With a new extension of the OPC UA specification, which Beckhoff played a prominent role in developing, the publisher/subscriber principle is being introduced into the established and standardized OPC UA communication protocol. One particular advantage is the much simplified configuration resulting from direct integration into the TwinCAT 3 environment. Communication is initiated directly from the TwinCAT 3 runtime, creating a real-time-capable communication channel via OPC UA. Conventional client/server applications are decoupled from one another in publisher/subscriber-based data communication and no longer need to “know” each other. The publisher simply sends its data, as a UDP multicast in this case, to a multicast group. The subscribers receive the data by subscribing to the multicast group instead of the actual device. These advantages can be utilized in all areas of machine design, plant engineering and building automation technology. This extension is expected to be finalized by the OPC Foundation in early 2017. Accordingly, Beckhoff plans a timely product release in TwinCAT 3.