Departmental Papers (CIS)

Date of this Version

April 2006

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

Additional Files

CISsupp.pdf (172 kB)
Supplemental file - cis_reports/124



Date Posted: 13 April 2006

This document has been peer reviewed.