Authors: Andreas Dittrich Rafael Rezende 14th European Workshop on Dependable Computing (EWDC), Coimbra, Portugal, May 15-16, 2013 Download: accepted version, the final publication is available at link.springer.com

Service-oriented architecture (SOA) has emerged as an approach to master growing system complexity by proposing services as basic building elements of system design. However, it remains difficult to evaluate dependability of such distributed and heterogeneous functionality as it depends highly on the properties of the enabling information and communications technology (ICT) infrastructure. Moreover, every specific pair service client and provider can utilize different ICT components, constituting for the user-perceived view of a service. We provide a model-driven methodology to automatically create reliability block diagrams of such views. Given a service description, a network topology model and a pair service client and provider, it identifies relevant ICT components and generates a user-perceived service availability model (UPSAM). We then use this UPSAM to calculate the steady-state availability of different views on an exemplary mail service deployed in the network infrastructure of University of Lugano, Switzerland.

	Authors: Andreas Dittrich Igor Kaitovic Cristina Murillo Rafael Rezende 27th IEEE International Symposium on Parallel Distributed Processing, Workshops and PhD Forum, IPDPSW 2013, Boston, MA, USA, May 20-24, 2013 Download: accepted version, final published version

An ever-increasing number of both functional and non-functional requirements has resulted in growing system complexity which demands new solutions in system modeling and evaluation. As a remedy, service-oriented architecture (SOA) offers 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 may 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.