“…In MBT, automation is based on a model, with the model often being statebased (see, for example, [1,2]). There has been particular interest in testing from a model in the form of a finite state machine (FSM) [3,4,5,6,7,8,9,10,11,12,13] or an input output transition system (IOTS) [14,15,16,17,18]; while the developer might produce a model in some other formalism, MBT tools often analyse an FSM or IOTS that represents the semantics of the model. This paper concerns testing from an IOTS model.…”