Avoiding faulty privileges in fast stabilizing rings

Most conventional studies on self-stabilization have been indifferent to the safety under convergence. This paper investigates how mutual exclusion property can be achieved in self-stabilizing rings even for illegitimate configurations. We present a new method which uses a state with a large state space to detect faults. If some faults are detected, every process is reset and not given a privilege. Even if the reset values are different between processes, our protocol mimics the behavior of Dijkstra's K-state protocol (1974). Then we have a fast and safe mutual exclusion protocol. A simulation study also shows its performance.