Reducing locating sequences for testing from finite state machines

Official URL: http://dx.doi.org/10.1145/2851613.2851831

When testing from a deterministic Finite State Machine specification M of an implementation N, state identification plays an essential role. In the case that M does not have a single input sequence to identify its states, state identification has to be performed by using a set of input sequences, elements of which need to be applied at the same state of N. Locating sequences have been proposed in the literature in order to guarantee that N is brought back to the same state over and over, in order to apply these input sequences. Although the lengths of locating sequences are exponential in general, there are some methods proposed in the literature to reduce their length. In this paper, we present an improved method for reducing the length of locating sequences. We give a formal description of our method and explain how the existing methods relate to our method.