An Introduction to Software Engineering and Fault Tolerance

1. Motivations for the Book Building systems that are trustful is one of the main challenges which software developers are facing. Dependability-related concerns have accompanied system developers since the first day these systems were built and deployed. Obviously various things have changed since then, including, the nature of faults and failures, the complexity of the systems, the services they deliver and the way our society uses these systems. But the need to deal with various threads (such as failed components, deteriorating environments , component mismatches, human mistakes, intrusions and software bugs) is still in the core of software and system research and development. As computers are now penetrating various new domains (including the critical ones) and the complexity of the modern systems is growing, achieving dependability remains central for system developers and users. Accepting that errors always happen in spite of all the efforts to eliminate the faults that might cause them is in the core of dependability. To