An early fault diagnosis agreement under hybrid fault model

Reliability is an important research topic in distributed systems. To achieve suitable reliability, the fault tolerance of distributed systems must be studied. One of the most important issues surrounding fault tolerance is the Byzantine Agreement (BA) problem. The goal of BA is to achieve a common agreement among fault-free processors even where faults persist. Likewise, fault diagnosis agreement (FDA) the purpose of which is to cause each fault-free processor to detect/locate a common set of faulty processors should be considered. In general, the FDA protocols need ⌊(n − 1)/3⌋ + 2 rounds of message exchange to detect/locate the faulty components even if the small of number of faulty processors exists. The number of messages results in a large protocol overhead. In this study, the FDA problem is solved early by an evidence-based fault diagnosis protocol that uses the minimum number of rounds characterized by dual failure of processors. In addition, the proposed protocol can detect/locate the maximum number of faulty processors in a network.