Reliability and safety analysis of fault tolerant and fail safe node for use in a railway signalling system

In this paper, we propose a Markov Reliability model for a transputer based fail safe and fault tolerant node for use in a network of distributed safety critical railway signalling systems. Using the Markov model we quantify the reliability and safety in terms of Probability of being in unsafe state, Probability of Safe shutdown during the useful life period and last phase of bath-tub curve. A fault analysis of the fail safe and fault tolerant node addressing Byzantine (malicious) faults with an extension of Byzantine Generalʹs problem is given.