Systematic Approach for QoS Estimation of Web Services

Quality of Service (QoS) assessment and prediction are an important issue in the development of distributed applications. The provision of web services with the same functionality gives rise to a need for implementation of more precise web service selection procedures. The paper introduces a new approach for web service selection that takes into account the web services' varying behavior defined by their constantly changing QoS properties as well as the ambiguous clients' QoS requirements. These uncertainties are formalized using respectively the probability theory and the theory of fuzzy sets. The feasibility of the approach is proved through a real scenario for web service selection.