Keywords: reliability, resilience, survival analysis, first passage time, FPT, extended evolutionary game theory, uncertain risk, latent risks, unobserved risks, unobservable risks, UUUR, three–layer survivability analysis, dynamic modelling, hybrid fault models, handicap principle, ecological stability, risk assessment
A unified definition for reliability, survivability and resilience inspired by the handicap principle and ecological stability
We propose a unified definition for reliability, survivability and resilience, which aims to synthesise the elements from existing definitions for survivability and also takes inspirations from the handicap principle and ecological stability. The unified definition is a four–tuple in the form of Survivability = [Resistance, Resilience, Persistence and Failure–Counter]. Resistance is largely equivalent to reliability and can be modelled with survival analysis (including competing risk analysis and multivariate survival analysis), which has some unique advantages over traditional reliability analysis such as dealing with censoring. Resilience can be formulated as a first passage time (FPT) problem; persistence can be defined as the minimum resistance level that a survivable system must maintain to be survivable. The unified definition offers a conceptual framework in which reliability and survivability can be quantitatively analysed with the approaches that we previously developed such as dynamic hybrid fault models, three–layer survivability analysis and extended evolutionary game theory.