Alderis@UCI
\n\t\t\t\t\t\tAnalysis Language for Distributed, Embedded, and Real-time Systems.
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Getting interested?
\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t\tFeel free to contact me if you have any questions or comments regarding the proposed method at gabe at uci dot edu.\n\t\t\t\t\t\t\t
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\n\t\t\t\t\t\t\t\tThe case study and the theoretic background behind the proposed method is explained in more detail in the following paper: Gabor Madl, Sherif Abdelwahed, Douglas C. Schmidt: Verifying Distributed Real-time Properties of Embedded Systems via Graph Transformations and Model Checking, Real-Time Systems, Special Issue: Invited Papers from the 25th IEEE International Real-Time Systems Symposium, Volume 33, Numbers 1-3, Pages 77-100, July 2006.
\n\n\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\n\t\t\t\tBoeing Bold Stroke Avionics Example
\n\t\t\t\t\t\t\n\t\t\t\t\t\t\tThis section illustrates the use of the Alderis language in a case study from the domain of avionics distributed real-time embedded (DRE) systems. Figure 1 shows the component-based architecture of the system, which is built upon the Boeing Bold Stroke real-time middleware. This application is deployed on a non-preemptive multiprocessor platform. As shown in Figure 1, this application is driven by five Timer components deployed on five CPUs.
\n\n\t\t\t\t\t\t\t\tFigure 1 - Aspects of the Bold Stroke Application
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\nComputations on different processors are driven by their respective\ntimers. Components, however, do not necessarily execute with the\ntimer's rate, as seen in the NAV_DISPLAY component's case. It\nis executed more often to serve remote requests than to serve local\nrequests on CPU_3.\n\n\t\t\t\t\t\t\t
Compositional Analysis
\n\n\t\t\t\t\t\t\t\nFigure 3 shows how we modeled the system in the Uppaal model checker tool. The application consits of 11 Task\ncomponents and 11 event channels, which 5 are local and used only for\nbuffering. The application is deployed on 5 processors. We have to model event channels explicitly (1)\nwhen we have to buffer events or (2) on remote event channels which\nhave measureable delays. All the event channels satisfy one of the\nabove conditions, except the timer's event channels that have been\nabstracted out in the model.\n\t\t\t\t\t\t\t
\n\n\t\t\t\t\t\t\t\nThe scheduling policies are represented by Schedulers in the\nDRE Semantic Domain. Since the Bold Stroke application is\ndeployed on a 5-processor architecture we define 5 schedulers as shown\non Figure 3. The schedulers get more complex\naccording to the scheduling policies. The automatic generation of the\nmodels provides a safe way to ensure the correct guard conditions and\nassignments. The timed automata model shown in Figure 3 corresponding \nto the Bold Stroke system shown in Figure 1 has been shown \nto be schedulable.\n\t\t\t\t\t\t\t
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Figure 3 - Generated timed automata models
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