UA Application Hierachies

Describes different scenarios where to use OPC UA applications, when there is more than one OPC UA data provider involved, potentially from several vendors. The scope of this version of the document is on the Client / Server Architecture of OPC UA. Later versions might also address Pub-Sub-scenarios. It describes different technology options and their support in the OPC UA specification, to address those application scenarios, and gives recommendations for the different scenarios.

The document is intended to be used by System Architects to get recommendations on how to apply OPC UA applications in their architecture.