FAULT INJECTION FOR DEPENDABILITY VALIDATION OF FAULT-TOLERANT COMPUTING SYSTEMS

This paper addresses the problem of the dependability validation of fault-tolerant computing systems and more specifically the validation of the fault-tolerance mechanisms. The presented approach is based on the use of fault-injection at the physical level on a hardware/software prototype of the system considered. The place of this approach in a validation directed design process, as well as its place with respect to related works on fault-injection, is clearly identified. The major requirements and problems related to the development and application of a validation methodology based on fault-injection are presented and discussed. The proposed methodology has been implemented through the realization of a general physical-fault injection tool (MESSALINE) whose usefulness is demonstrated by its application to the experimental validation of a subsystem of a computerized interlocking system for railways control applications.