Getting for ready data of OpenSCADA — gateway
Having familiarised with the typical mechanisms for obtaining the data, described in the previous sections, you must imagine already the total amount of work on their getting and processing, that is — formalising and obtaining this data in the SCADA-system data model. If you add here the task of creating these data at the PLC level — the data model of freely programmable PLC, and transforming it in the data model of the exchanging protocol, then you should notice a triple data transformation here. About the transformation in the protocol data model — serialisation, this is determined by the physical properties of the communication channels and is carried out automatically, but the formation of the PLC data model and SCADA-system data model is carried out by the programmer of the PLC and the SCADA-system, respectively. Moreover, this work has much in common, especially if performed by one person or organisation, and therefore there should be mechanisms for its unification.