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Network-Code Machine: Programmable Real-Time Communication Schedules
Departmental Papers (CIS)
  • Sebastian Fischmeister, University of Pennsylvania
  • Oleg Sokolsky, University of Pennsylvania
  • Insup Lee, University of Pennsylvania
Date of this Version
Document Type
Conference Paper
Copyright 2006 IEEE. Reprinted from Proceedings of the 12th IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS'06)

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Distributed hard real-time systems require guaranteed communication. One common approach is to restrict network access by enforcing a time-division multiple access (TDMA) schedule.The typical data representation of offline-generated TDMA schedules is table-like structures. This representation, however, does not permit applications with dynamic communication demands, because the table-like structure prevents on-the-fly changes during execution. A common approach for applications with dynamic communication behavior is dynamic TDMA schedules. However, such schedules are hard to verify, because they are usually implemented in a programming language, which does not support verification. Network code is a behavioral model for specifying real-time communication schedules. It allows modeling arbitrary time-triggered communication schedules with on-the-fly choices, and it is also apt for formal verification. In this work, we present network code and show how we can use a model checker to verify safety properties such as collision-free communication, schedulability, and guaranteed message reception. We also discuss its implementation in RTLinux and provide performance measurements.
  • Real time systems,
  • scheduling,
  • time division multiaccess,
  • networks,
  • software verification and validation
Citation Information
Sebastian Fischmeister, Oleg Sokolsky and Insup Lee. "Network-Code Machine: Programmable Real-Time Communication Schedules" (2006)
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