Testing deterministic implementations from nondeterministic FSM specifications

In this paper, conformance testing of protocols specified as nondeterministic finite state machines is considered. Protocol implementations are assumed to be deterministic. In this testing scenario, the conformance relation becomes a preorder, so-called reduction relation between FSMs. The reduction relation requires that an implementation machine produces a (sub)set of output sequences that can be produced by its specification machine in response to every input sequence. A method for deriving tests with respect to the reduction relation with full fault coverage for deterministic implementations is proposed based on certain properties of the product of specification and implementation machines. Keywords Conformance testing, test derivation, fault detection, I/O nondeterministic FSMs, equivalence and reduction relations 1 INTRODUCTION Conformance testing of protocol implementations is often formalized as the FSM equivalence problem (Moore, 1956) and (Hennie, 1964). In particular, we ..