Protocols for Failure Diagnosis Event Systems

We address the problem of failure diagnosis in discrete event systems with decentralized information. We propose a coordinated decentralized architecture consisting of two local sites communicating with a coordinator that is responsible for diagnosing the failures occurring in the system. We extend the notion of diagnosability, originally introduced in [l] for centralized systems, to the proposed coordinated decentralized architecture. We specify three protocols that realize the proposed architecture. We analyze the diagnostic properties of these protocol. The key features of the proposed protocols are: (i) they achieve, each under a set of assumptions, the same diagnostic performance as the centralized diagnoser; and (ii) they highlight the performance vs. complexity tradeoff that arises in coordinated decentralized architectures.