The most typical use of OPC Data Client-UA involves a thick-client user application written in one of the Microsoft .NET languages. This application uses the types from OPC Data Client-UA object model, and accesses data within OPC servers that are located on remote computers on the same LAN (Local Area Network) or on WAN (Wide Area Network) or on the Internet. The communication with the target OPC server is performed by means of Web Services.

The following picture shows how the individual pieces work together: