Extending Compositional Message Sequence Graphs

We extend the formal developments for message sequence charts (MSCs) to support scenarios with lost and found messages. We define a notion of extended compositional message sequence charts (ECMSCs) which subsumes the notion of compositional message sequence charts in expressive power but additionally allows to define lost and found messages explicitly. As usual, ECMSCs might be combined by means of choice and repetition towards (extended) compositional message sequence graphs. We show that despite extended expressive power model checking of monadic second-order logic (MSO) for this framework remains to be decidable. The key technique to achieve our results is to use an extended notion for linearizations. Comments University of Pennsylvania Department of Computer and Information Science Technical Report No. MSCIS-02-09. This technical report is available at ScholarlyCommons: http://repository.upenn.edu/cis_reports/171 Extending Compositional Message Sequence Graphs Benedikt Bolligl, Martin Leucker2*, and Philipp Lucas' Lehrstuhl fiir Informatik 11, Aachen University of Technology (RWTH), Germany {bollig,phlucas}Qi2. inf ormatik. rwth-aachen. de Dept. of Computer and Information Science, University of Pennsylvania, USA leuckerQcis.upenn.edu Abstract. We extend the formal developments for message sequence charts (MSCs) to support scenarios with lost and found messages. We define a notion of extended compositional message sequence charts (ECMSCs) which subsumes the notion of compositional message sequence charts in expressive power but additionally allows to define lost and found messages explicitly. As usual, ECMSCs might be combined by means of choice and repetition towards (extended) compositional message sequence graphs. We show that^-despite extended expressive power-model checking of monadic second-order logic (MSO) for this framework remains to be decidable. The key technique to achieve our results is to use an We extend the formal developments for message sequence charts (MSCs) to support scenarios with lost and found messages. We define a notion of extended compositional message sequence charts (ECMSCs) which subsumes the notion of compositional message sequence charts in expressive power but additionally allows to define lost and found messages explicitly. As usual, ECMSCs might be combined by means of choice and repetition towards (extended) compositional message sequence graphs. We show that^-despite extended expressive power-model checking of monadic second-order logic (MSO) for this framework remains to be decidable. The key technique to achieve our results is to use an extended notion for linearizations.