Simple finite-state fault detectors for communication networks

This work provides a framework for approaching the problem of fault detection in communication processes. Communication processes are modeled as finite state machines (FSMs), and the authors´ model consists of two FSMs, one observing part of the behavior of the other. The authors prove that specific classes of faults are detectable, and give a procedure for constructing detectors, but the design of the minimum alphabet detector is NP-complete. An example applicable to the 802.2 protocol is provided