Predicting Compliance of WSLA Contracts Using Automated Model Creation

Service level agreements (SLAs) are designed to be monitorable contracts between a provider and consumer of a service. It is of interest to determine if such SLAs can also be used as input to a predictive model, e.g., a discrete-event stochastic model. For that purpose we study in this paper WSLA, the web service level agreement language, an SLA specification language tailored to web services. We provide a mapping from WSLA to metrics defined in the discrete event stochastic modeling formalism SDES (stochastic discrete event systems). We provide extensions to the commonly used SPNP tool to automate much of this process, such that given a WSLA document, the mapped SDES metrics can be derived automatically as much as possible. We will specify precisely what the modeler inputs during this process, and demonstrate the use of our tool for WSLA compliance prediction. © 2010 University of Newcastle upon Tyne. Printed and published by the University of Newcastle upon Tyne, Computing Science, Claremont Tower, Claremont Road, Newcastle upon Tyne, NE1 7RU, England. Bibliographical details YASSIN KASSAB, R., VAN MOORSEL, A Predicting Compliance of WSLA Contracts Using Automated Model Creation [By] Yassin Kassab, R., van Moorsel, A. Newcastle upon Tyne: University of Newcastle upon Tyne: Computing Science, 2010. (University of Newcastle upon Tyne, Computing Science, Technical Report Series, No. CS-TR-1204)

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