QoS-Aware Semantic Service Selection: An Optimization Problem

Abstract

In order to select the best suited service among a set of discovered services, with respect to QOS parameters, a user have to state his or her preferences, so services can be ranked according to these QOS parameters. Current Se- mantic Web Services ontologies do not support the defini- tion of QOS-aware user preferences, though there are some proposals that extend those ontologies to allow selection based on those preferences. However, their selection algo- rithms are very coupled with user preferences descriptions, which are defined without semantics or at a different seman- tic level than service functionality. In this work, we present a service selection framework that transforms user prefer- ences into an optimization problem where the best service is selected. This framework is based on an ontology that conceptualizes these user preferences. Thus, we use a very expressive solution decoupled with the concrete selection technique by using XSL transformations, while describing QOS-aware user preferences at the same semantic level of functional preferences.