Vertical and horizontal communication between various components of different manufacturers of automation systems becomes a lot easier using OPC-UA. It defines an uniform interface to realize complex control systems and structures. Design paradigm is a service oriented architecture (SOA). OPC-UA becomes a platform and supplier independent standard for IoT systems based on established communication infrastructures. It provides integrated communication between sensor/actor and cloud. emlix evaluates appropriate OPC UA stacks and undertakes the task to implement OPC UA server and client. OPC-UA based systems designed by emlix are to be found in innovative solutions for connection of various control systems with SCADA systems as well as remote with ERP systems.