Fault tolerance requirements analysis using deviations in the CORRECT development process

Abstract

Current requirements analysis methods focus on the functional properties of fault free systems. It is known that, regardless of the type of software system, many faults are made during engineering and that these faults may conduct system errors and then system failures. We believe that faulty engineering activities, as well as correct activities, should be given precedence during software development. In this paper we present CORA, which is the analysis phase for the CORRECT methodology. CORA introduces semi-formal models based on UML and OCL that allow for the specification of normal system behaviors, as well as abnormal behaviors, together with their associated recovery strategy. CORA proposes to specify fault-tolerant systems using a domain model as a custom UML class diagram and an activity model as a custom UML activity diagram. The deviation and recovery strategies are expressed explicitly in a specific section of the CORA Activity Diagram. This paper introduces CORA conceptually and it explicitly defines the syntax and semantics of the proposed analysis models. We also use a running example to illustrate our approach. © 2009 Springer Berlin Heidelberg.