Dependability of computer systems: concepts, limits, improvements

Our society is faced with an ever increasing dependence on computing systems, which lead to questions about the limits of their dependability, and to attempt to identify avenues for improving the situation. In order to respond to these questions, a global conceptual and terminological framework is needed, which is first given. The limits in dependability are then addressed from technical and financial viewpoints. The identification of design faults as the current major bottleneck for dependability leads to: a) address the limits in software reliability and in fault tolerance effectiveness, and to b) suggest a dependability explicit development model.