A comparative analysis of network dependability, fault-tolerance, reliability, security, and survivability

A number of qualitative and quantitative terms are used to describe the performance of what has come to be known as information systems, networks or infrastructures. However, some of these terms either have overlapping meanings or contain ambiguities in their definitions presenting problems to those who attempt a rigorous evaluation of the performance of such systems. The phenomenon arises because the wide range of disciplines covered by the term information technology have developed their own distinct terminologies. This paper presents a systematic approach for determining common and complementary characteristics of five widely-used concepts, dependability, fault-tolerance, reliability, security, and survivability. The approach consists of comparing definitions, attributes, and evaluation measures for each of the five concepts and developing corresponding relations. Removing redundancies and clarifying ambiguities will help the mapping of broad user-specified requirements into objective performance parameters for analyzing and designing information infrastructures.