An improved RCP-method for protocol test generation using backward UIO sequences

This paper generalizes the notion of UIO sequences used for generating protocol testing sequences. The authors call these sequences forward UIO sequences (or simply F-UIO sequences), because a unique output sequence is to be observed by applying a UIO sequence starting from the state with which this UIO sequence is associated. This paper associates with each state another sequence called backward UIO (or simply B-UIO) sequence such that a unique output sequence is to be observed by applying this sequence with this state being the ending state. Using B-UIO sequences, this paper improves the RCP-method (1988)