Dependability Assessment

Abstract

Dependability has been defined as ‘a property such that reliance can justifiably be placed on the service delivered by a product’ in its utilization context. Such a definition containing the word ‘justified’ implies means, which allow the evaluation or measuring of the reliance. The numerous assessment approaches which exist are typically classified into two groups. The first one, called quantitative dependability assessment, consists in defining dependability measurements and techniques to obtain the values of these measurements. The second one, called qualitative dependability assessment, is based on dreaded events and techniques to evaluate their effects and their potentiality. These events are faults, errors, failures and their consequences. Naturally, some of these techniques can be used for quantitative as well as for qualitative assessment.