Interchangeable Scheduling Policies in Real-Time Middleware for Distribution

  • Juan López Campos
  • J. Javier Gutiérrez
  • Michael González Harbour
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4006)


When a middleware layer is designed for providing semi-transparent distribution facilities to real-time applications, a trade-off must be made between the expressiveness and control capabilities of the real-time parameters used, and the simplicity of usage. Middleware specifications such as RT-CORBA or Ada’s Distributed Systems Annex (DSA) rely on the use of priorities to map the timing requirements of the application, thus restricting the possible scheduling policies. This paper presents a generic technique to express complex scheduling and timing parameters of distributed transactions, allowing real-time middleware implementations to change their scheduling policies for both the processing nodes and the networks. The technique has been tested in an implementation of Ada’s DSA, providing two interchangeable policies: a fixed-priority scheduler, and a complex contract-based flexible scheduler.


Schedule Policy Reply Message Remote Node Query Message Transactional Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Juan López Campos
    • 1
  • J. Javier Gutiérrez
    • 1
  • Michael González Harbour
    • 1
  1. 1.Departamento de Electrónica y ComputadoresUniversidad de CantabriaSantanderSpain

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