The recent trend towards applying component-based and model-driven approaches also to the development of safety-critical real-time embedded systems, opens new possibilities for model-level analysis of aspects that traditionally are analysed very late in the development when the system has been fully implemented. For real-time systems, the temporal aspect is as important as the functional to the overall correctness of the system, and thus timing analysis in different forms play a key role in their development. This paper presents the timing analysis of ProCom, a component model specifically targeting distributed real-time embedded systems, focusing in particular on three methods for compositional model-level analysis of worst-case execution time.