Refusal testing for MIOTS with nonlockable output channels

This paper extends the refusal testing for multi input-output systems (MIOTS) to make it also applicable to test those implementations with nonlockable output channels. Starting with the MIOTS refusal testing theory, we distinguish two types of output channels: lockable and nonlockable, and develop a more general multi input-output refusal testing relation. A test generation algorithm is proposed to derive a complete test suite from a specification.