Dynamic Web Services Composition Based on QoS

Abstract—Service Oriented Architecture has received much of interest from architects and decision makers trying to profit from its different great advantages. Within SOA (Service Oriented Architecture), applications are constructed from reusable specialized components available on the network named web services. Web services composition is one of the most useful assets of this paradigm, thus it is a hot topic receiving more and more attention in order to propose better approaches dealing with WSC (Web Service Composition) issues and requirements. Efforts advanced in this topic may be classified according to the degree of automation in its creation or the binding time (design time or runtime). However, web services must, generally, operate in large scale business environment that are seldom static. Despite the great number of studies exploring the dynamic composition, few are those taking into account and dealing with quality of service rate which tend to be volatile. Thus, non-functional properties have to be continuously monitored to select the best web service at invocation time. In this paper, we introduce a QoS (Quality Of Service) based web service composition approach and we focus especially in a web service discovery and selection strategy whose goal is to have as much information as possible about available web services and specifically up to date knowledge of current QoS parameters values so that presently the best web service is selected