Validation of fault tolerance mechanisms of an onboard system

Fault tolerance is of importance to increase the dependability of computer systems. However, it is hard to be evaluated and validated, which will be either time-consuming or costly. Fault injection is an effective method to validate fault tolerance mechanisms. Among different fault injection techniques, software-implemented fault injection (SWIFI) is the most promising one. Although interesting, major drawbacks of existing SWIFI are that temporal and spatial overheads induced into target systems will influence its behavior. In this paper, fault tolerance of an onboard system is tested by a new SWIFI technique which will not induce any additional overheads into the target system under test. The technique is based on embedded processor debug interface standard, Nexus, which ensures that faults are injected into the target system with its behavior being traced while not altering normal execution of the target system.