In an Industry 4.0 or IoT application, a virtual representation must be created on a central service platform for each of the individual components. For this task, SSV Software offers a modular connection system consisting of a middleware server and various remote access gateways. The server and gateways can be used to interconnect individual modules and subsystems at different locations using a virtual private network (VPN) to create a higher-level network system. Within the VPN, the components can communicate with each other via a standardized software interface using so-called Real Time Data Channels (RTDC). When developing the RTDC, the provider was guided by the Architectural Reference Model (ARM) of the European research project IoT-A (Internet of Things Architecture). MQTT is used in addition to HTTP. The SSV Connector API (SSV/CAPI) serves as an additional integration interface. It can be used, for example, to integrate field devices with MPI, Modbus or other legacy interfaces or protocols into IoT solutions without additional gateways. In this case, the middleware server acts as a data broker for the different systems.