A Language for Task Orchestration and Its Semantic Properties

  • David Kitchin
  • William R. Cook
  • Jayadev Misra
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4137)


Orc is a new language for task orchestration, a form of concurrent programming with applications in workflow, business process management, and web service orchestration. Orc provides constructs to orchestrate the concurrent invocation of services – while managing time-outs, priorities, and failure of services or communication. In this paper, we show a trace-based semantic model for Orc, which induces a congruence on Orc programs and facilitates reasoning about them. Despite the simplicity of the language and its semantic model, Orc is able to express a variety of useful orchestration tasks.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • David Kitchin
    • 1
  • William R. Cook
    • 1
  • Jayadev Misra
    • 1
  1. 1.The University of Texas at Austin 

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