5.5 Characterization Set
Most methods for generating tests from FSMs make use of an important set known as the characterization set. This set is usually denoted by W and is sometimes referred to as the W-set. In this section, we explain how one can derive a W-set, given the description of an FSM. Let us examine the definition of the W-set.
The characterization set W for a minimal FSM Μ is a finite set of strings over the input alphabet of Μ such that for each pair of states (r, s) in Μ there exists at least one string in W that distinguishes state r from state s.
Let Μ = (X, Y, Q, q1, δ, O) be an FSM that is minimal and complete. A characterization set for M, denoted as W, is a finite set of input sequences that distinguish the behavior of ...