Reliability and System Design

Abstract

The reliability of an extensive software system is essentially determined during the design stage. If the system design is poor, that is, without understandable structure, then in the majority of cases it is not possible to provide a highly reliable product by later corrections. If, on the other hand, more effort is put into the elimination of errors during the design phase, then considerable savings will be made during later debugging. In this chapter, the prevention of system design errors is investigated. In the first section the corner-stone of all software systems, the sequential processes analysed in detail. When a number of processes run quasi-simultaneously, a number of new problems and sources for error appear; these are dealt with in the subsequent section. In the final section of the chapter, programming is considered from the point of view of reliability.