OPC UA is an open and royalty free standard designed as a universal communications protocol. It is also available as IEC 62541.
OPC UA has a broad scope which delivers economies of scale for application developers. When combined with powerful semantic models, OPC UA makes it easier for end users to access data via generic commercial application. It provides an information modelling framework that allows application developers to represent their data in a way that makes sense to them.
The OPC UA model is scalable from small devices to Enterprise Resource Planning (ERP) systems. OPC UA devices process information locally and then provides that data in a consistent format to any application requesting data. For a more complete overview see Part 1 – Concepts.