Network Performance Evaluation for Distributed Embedded Systems Using Feature Models

In this paper, we focus on networked, embedded systems which may contain numerous electronic control units, connected by multiple network busses. Furthermore, such embedded systems support many runtime configurations. The main problem is to determine the network resource needs of all variations permitted at runtime, i.e. to calculate the worst case resource needs. We describe the runtime variability of such systems by means of a runtime feature model and then derive a network performance model in a stepwise way. The mappings from the feature level leads to a data flow model, then to the component/hardware level, where we perform a detailed network analysis based on Network Calculus. Thus, we can decide in an early design stage, whether a given network topology fits the requirements of a given software architecture. We show then, by an example, (i) that the performance of this component/hardware model can be analyzed using network calculus and (ii) that our approach can significantly reduce resource overestimation compared to a static evaluation.