1. Introduction - Laboratory for Reliable Computing

Fault• Fault: a physical defect in a circuit/system− Permanent fault: a fault that is continuous and stable, whosenature do not change before, during, and after testing∗ Affecting the functional behavior of the system permanently∗ A.k.a. hard fault or solid fault∗ Usually quite localized∗ Can be modeled− Temporary fault: a fault that is present only part of the time,occurring at random moments and affecting the system forfinite, but unknown, intervals of time∗ Transient fault: caused by environmental conditions∗ No well-defined fault model∗ Called soft error in RAM∗ Often assumed no permanent damage was done− Intermittent fault: caused by non-environmental conditions∗ Often repeatable∗ Can use permanent fault models and repeated test with stressm01intro7.02 Cheng-Wen Wu, NTHU 11