CONCUR 2006 – Concurrency Theory

Volume 4137 of the series Lecture Notes in Computer Science pp 477-491

A Language for Task Orchestration and Its Semantic Properties

  • David KitchinAffiliated withThe University of Texas at Austin
  • , William R. CookAffiliated withThe University of Texas at Austin
  • , Jayadev MisraAffiliated withThe University of Texas at Austin

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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.