Maintaining consistency among distributed control nodes

This work presents how state consistency among distributed control nodes is maintained in the presence of faults. We analyze a fault-tolerant semi-synchronous architecture concept of a distributed flight control system (DFCS). This architecture has been shown robust against transient faults of continuous signals through inherent replica consistency. This approach necessitates neither atomic broadcast nor replica determinism. Here, we extend the analysis of replica consistency property to confirm robustness against transient faults in discrete signals in the presence of a single permanent fault in the DFCS components. The paper is based on a case study on JAS 39 Gripen, a modern fourth generation multi purpose combat aircraft, presently operating with a centralized FCS. Our goal is to design the DFCS fault management mechanisms so that the distributed treatment of faults corresponds to the existing nondistributed FCS.