Model-Driven Evaluation of User-Perceived Service Availability
Ribeiro Rezende R.
Service-oriented architecture (SOA), which proposes services as basic building elements of system design, has emerged as an approach to master growing system complexity. 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 examplary mail service deployed in the network infrastructure of University of Lugano.