Abstract

Often the systems our societies depend upon are built in such a way as to result too inflexible and intolerant to changes. The deployment of such systems in environments where change is the rule rather than the exception leads to situations where quality-of-service and quality-of-experience are strongly and negatively affected. As a result, there is an urgent need to investigate structuring techniques, architectures, algorithms, tools, and paradigms for the expression and the management of adaptive-and-dependable software systems, i.e., software, devices, and services that are built so as to sustain an agreed-upon quality-of-service and quality-of-experience despite the occurrence of potentially significant and sudden changes or failures in their infrastructure and surrounding environments. This need is the core business of the research line "Adaptive-and-dependable software systems" (ADSS) within the PATS research group of the University of Antwerp and IBBT, both of them in Belgium. This is carried out through the design, development, and evaluation of architectures and techniques to structure our computer systems as adaptive entities able to constantly re-optimize in view of changes, both exogenous (i.e. environmental) and endogenous (that is, pertaining to internal assets). Such changes include failures threatening the services supplied by those systems. In this talk I will describe in particular a reflective software architecture, developed in our task force, that may be used to design dependable systems able to detect and react to changes in the fault- and system-model.