ABSTRACT
In our discussion of degradation faults, therefore, we limit our attention to fault tolerance and, within that topic, to the aspects of the problem that are important to us as software engineers or computer engineers. Our goal is not to develop or analyze fault-tolerant structures that might be used for coping with degradation faults, although we will describe them. Our goal is to understand how such techniques impact software, both its development and its operation. This impact is quite extensive. The result of having to deal with degradation faults affects software in two ways:
Target Platform Architecture. The target platform upon which the software executes can be a lot more complicated than might be expected. Equipment is present that would not be needed if our goal was merely to execute the software. As a minimum, the software has to execute properly with this target.
