**2. Information chain according to the shell model**

In order to achieve real-time control, it is essential that the data acquisition, computation, and provision of the next instruction occur at a speed that is at least twice as fast as the process being controlled [6].

Accordingly, all interaction levels in IoT must be measured for their QoS (Quality of Service) in addition to Round-Trip Times (RTT). Only then can a reliable decision be made as to which processes can be controlled in real-time. Alternatively, the process speeds can be adjusted to the determined real-time characteristics (or real-time limits) of the respective interaction levels. The speed at which the autonomous vehicle performs over the measured interaction level should not exceed half of its real-time capability.

**Figure 1** gives a rough overview of the information flow to the IoT interaction levels and back.

**Figure 1.** *Shell model for the IoT interaction levels [9].*

Our objective is to propose a software development methodology for real-time IoT interactions. The term "propose" implies that this is a sketch that does not claim to be complete, but rather represents one of many possible solutions. Given the enormous complexity of the subject, it cannot be fully represented within the scope of this framework.
