Secure IoT devices are the basis for the digitization of Industry 4.0. Even if the connection of IoT devices via (international) cloud provider simplifies the handling for manufacturers (e.g. in servicing), the dangers for cloud-connected IoT devices and all users must be taken into account. A single successfully attacked IoT device can mutate into an attack vector for all devices connected to this cloud. Having your own in-house cloud solution counteracts the problems in several ways. The "Security by Isolation" (SBI) model from the Austrian flagship research project IoT4CPS represents such a solution. The Sec³ Secure Cloud Connecting System is based on this model and avoids uncontrolled access to data. The system offers maximum security for machi ...