OPC UA (Unified Architecture)

OPC UA (Open Platform Communications – Unified Architecture) is a manufacturer- and platform-independent standard that enables the cross-company industrial com­mu­ni­ca­tion of tomorrow. Often re­fer­red to by research and industry as a key tech­nol­ogy, OPC UA standardizes the exchange of data and information in the im­ple­men­ta­tion of Industry 4.0 concepts.

This allows components from different system suppliers to be combined and organized in one system without any further precautions. In addition to simplified machine communication (M2M), vertical integration – from the field device via the ERP system to the cloud – also takes place, thus enabling a continuous network.


The architecture is based on the client-server and the publisher-subscriber model, which meets different tasks. The already in the architecture integrated security fea­tures deal with the levels of user, app­li­ca­tion and transport security. In addition to the trans­mission of the machine data, they are also described seman­tic­ally in a machine-readable manner. This creates the basis for semantic inter­oper­a­bil­ity and the sensible use of the data.

The so-called Companion Specifications of the platform are information models, where­by industry-specific models can be stan­dar­dized and thus pres­ented as uni­form and in­de­pen­dent data. The ethernet-­based com­mu­ni­ca­tion standard sim­pli­fies the im­ple­men­ta­tion of mo­du­lar pro­duc­tion sys­tems (plug and play) and enables asso­ciated time and cost savings.