Architecting resilient computing systems: Overall approach and open issues

Resilient systems are expected to continuously provide trustworthy services despite changes coming from the environment or from their specifications. This definition is based on the work carried out within the European Network of Excellence, ReSIST. This paper is focussed on a methodology to provide adaptation mechanisms meant to ensure dependability while coping with various modifications of applications´ and system´s context. To that aim, a representation of dependability-related attributes that may evolve during system lifecycle is proposed, and why this representation is useful to provide adaptation of dependability mechanisms at run time is shown. In this paper any application attached to one or several fault tolerance mechanisms is considered. Among the evolution scenarios that can occur during the operational life of a fault tolerant application, we focus on those that may have an impact on the fault tolerance mechanisms.