A Model for Evaluation of User-Perceived Service Properties

An ever-increasing number of both functional and non-functional requirements has resulted in growing system complexity which demands for new solutions in system modeling and evaluation. As a remedy, service-oriented architecture (SOA) proposes services as basic building elements of system design. Service dependability is highly dependent on the properties of the underlying information and communications technology (ICT) infrastructure. This is especially true for the user-perceived dependability of a specific pair service client and provider as every pair can utilize different ICT components. We provide a model for the description of ICT components and their non-functional properties based on the Unified Modeling Language (UML). Given a service description, a network topology model and a pair service client and provider, we propose a methodology to automatically identify relevant ICT components and generate a user-perceived service infrastructure model (UPSIM). We demonstrate the feasibility of the methodology by applying it to parts of the service network infrastructure at University of Lugano (USI), Switzerland. We then show how this methodology can be used to facilitate user-perceived service dependability analysis.