With the standardization of UML (Unified Modeling Language), the hard point of the profusion of object-oriented formalisms has fallen, facilitating the introduction of these technologies into the industrial domain. The work in progress at the OMG (Object Management Group) to introduce points relating to the real time domain into the evolutions of the standard shows, on the one hand, that there is a strong interest in this application domain and, on the other hand, that the current proposals still need to be refined to fully satisfy needs.
The aim of this text is to provide an overview of the native UML concepts already available as standard and which can be used to model real-time systems. In particular, we will briefly describe the various supports provided by UML for modeling concurrency, behavior, communications and quantitative temporal information.
A second article, "UML for real time. Applications" will illustrate these concepts on a case study, highlighting a proposed methodological approach to raising the trickiest points in using UML.