Creating and developing OV-6b operational state transition diagrams
OV-6b Operational State Transition diagrams, drawn using the IDEF3 OSTN (Object State Transition Network), describe a situation from an object-centered view; that is, a participating object is the focus of attention.
Operational State Transition diagram elements
OV-6b Operational State Transition diagrams consist of the following symbols: object states, transitions, state junctions, and referents.
Object states
An object state is the basic organizing structure of the object state transition description. An object state in the IDEF3 process method is any physical or conceptual thing that is recognized and referred to by participants in the domain as a part of their description of what happens in their domain. Identifying, characterizing, and naming object states is a necessary step in the creation of Operational State Transition descriptions.
Object states appear as labeled circles.
Transitions
Transitions represent allowable changes between states. One of the first steps in the development of an OV-6b Operational State Transition is to identify all possible states in which the object can exist. Though a real-world object often evolves through a continuum of states, an Op State Transition diagram focuses on those distinguished states that are of particular interest to the domain expert. For each of these states, the Op State Transition diagram supports the specification of the following conditions:
▪The conditions that characterize the state
▪The conditions that will permit a transition into the state (entry conditions)
▪The conditions that need to hold for the object to transition out of the state (exit conditions)
State junctions
State Junctions indicate the logic of the transition between states.
Referents
Referents represent objects or information critical to the completion of a scenario or Process Flow diagram. In an Operational State Transition diagram, referents allow you to do the following tasks:
▪Span multiple pages or loop back in a diagram layout
▪Tie in specific examples of referenced data or objects (for example, screen layouts)
▪Associate special constraint sets to object states; that is, associate an elaboration with an object state to describe additional facts, constraints, or decision logic which limit how that object state works
▪Form references or links between OV-6b Op State Transition diagrams and OV-6a Op Rules Model diagrams.
Scenarios
Many of the critical characteristics of an architecture are only discovered when an architecture's dynamic behaviors are defined and described.
A scenario can be thought of as one of the following items:
▪A particular recurring situation in an organization for which documentation is required
▪A set of situations which describes a typical class of problems addressed by an organization or system