The innovative concepts and procedures of the Fourth Industrial Revolution (Industry 4.0) are creating entirely new possibilities for cooperation – especially on a technical level. Systems, machines and products interact, exchange data and information, communicating with each other all the while.

It makes no difference whether communication takes place with a machine in the same factory hall or with a system in a plant on the other side of the world so that the boundaries for trust are exceeded. However, this can only work if technical communication mechanisms ensure that Industry 4.0 components (assets) can communicate in a secure and interoperable manner and thereby enable trust across company boundaries.

OPC UA (OPC Unified Architecture) is an architecture used to describe and exchange machine data. In this respect, OPC UA is more than just a communication protocol – the architecture also includes data models and interaction concepts. OPC has been successfully used in automation technology for some time now. The further development of OPC UA is today widely supported; it has been recommended as an important technology in the implementation strategy of the Industry 4.0 platform and is part of the “Criteria for Industry 4.0 Products” of the ZVEI manufacturers’ association. This paper focuses accordingly on OPC UA.