Efficient and modular modeling of hierarchical multimedia objects by using time ERPN+

In order to design and analyse complex real time systems, we improve the communication mechanism of Time Recursive Petri Net model that we have proposed in previous works. First, we show that the new version, named Time ERPN⁺, enables to obtain very compact patterns of dynamic multi-threaded systems. To show the great modeling capacities of Time ERPN⁺, we model and analyse the temporal behavior of hierarchical SMIL multimedia objects. We offer a very modular modeling which exactly reflects the SMIL documents temporal structures where a special attention is given to the synchronization relations between objects having distinct time references. The reachability analysis of Time ERPN⁺ allows to verify the temporal consistency properties of SMIL documents. Furthermore, our model can be used efficiently to define scheduling policies.