Distributed Fault diagnosis of a Ring of Processors

Based on the theory of system level diagnosis pioneered by Preparata, Metze and Chien [1], we study fault diagnosis of a ring of processors. We use the comparison based model of Chwa and Hakimi [4]. It is shown that the processors in a ring can be diagnosed uniquely if, and only if, the faults are distributed in a certain manner. We present algorithms to diagnose the faulty processors when these requirements are satisfied. These algorithms permit distributed implementation on both unidirectional and bidirectional rings.