University of SaskatchewanHARVEST
  • Login
  • Submit Your Work
  • About
    • About HARVEST
    • Guidelines
    • Browse
      • All of HARVEST
      • Communities & Collections
      • By Issue Date
      • Authors
      • Titles
      • Subjects
      • This Collection
      • By Issue Date
      • Authors
      • Titles
      • Subjects
    • My Account
      • Login
      JavaScript is disabled for your browser. Some features of this site may not work without it.
      View Item 
      • HARVEST
      • Electronic Theses and Dissertations
      • Graduate Theses and Dissertations
      • View Item
      • HARVEST
      • Electronic Theses and Dissertations
      • Graduate Theses and Dissertations
      • View Item

      Model aware execution of composite web services

      Thumbnail
      View/Open
      Thesis_KZurowska_final_2.pdf (3.297Mb)
      Date
      2008
      Author
      Zurowska, Karolina
      Type
      Thesis
      Degree Level
      Masters
      Metadata
      Show full item record
      Abstract
      In the Service Oriented Architecture (SOA) services are computational elements that are published, discovered, consumed and aggregated across platform and organizational borders. The most commonly used technology to achieve SOA are Web Services (WSs). This is due to standardization process (WSDL, SOAP, UDDI standards) and a wide range of available infrastructure and tools. A very interesting aspect of WSs is their composeability. WSs can be easily aggregated into complex workflows, called Composite Web Services (CWSs). These compositions of services enable further reuse and in this way new, even more complex, systems are built.Although there are many languages to specify or implement workflows, in the service-oriented systems BPEL (Business Process Execution Language) is widely accepted. With this language WSs are orchestrated and then executed with specialized engines (like ActiveBPEL). While being very popular, BPEL has certain limitations in monitoring and optimizing executions of CWSs. It is very hard with this language to adapt CWSs to changes in the performance of used WSs, and also to select the optimal way to execute a CWS. To overcome the limitations of BPEL, I present a model-aware approach to execute CWSs. To achieve the model awareness the Coloured Petri Nets (CPN) formalism is considered as the basis of the execution of CWSs. This is different than other works in using formal methods in CWSs, which are restricted to purposes like verification or checking of correctness. Here the formal and unambiguous notation of the CPN is used to model, analyze, execute and monitor CWSs. Furthermore this approach to execute CWSs, which is based on the CPN formalism, is implemented in the model-aware middleware. It is also demonstrated how the middleware improves the performance and reliability of CWSs.
      Degree
      Master of Science (M.Sc.)
      Department
      Computer Science
      Program
      Computer Science
      Supervisor
      Deters, Ralph
      Committee
      Zhang, W. J. (Chris); Vassileva, Julita; McCalla, Gordon I.
      Copyright Date
      2008
      URI
      http://hdl.handle.net/10388/etd-08012008-123042
      Subject
      performance
      model
      Coloured Petri Nets
      composite web services
      Collections
      • Graduate Theses and Dissertations
      University of Saskatchewan

      University Library

      The University of Saskatchewan's main campus is situated on Treaty 6 Territory and the Homeland of the Métis.

      © University of Saskatchewan
      Contact Us | Disclaimer | Privacy