UPDMRTF — Subject of a State Machine

Issue State machine issue: UML states the subject of a state machine can be behavior or structural: “The StateMachines package defines a set of concepts that can be used for modeling discrete event-driven Behaviors using a finite state-machine formalism. In addition to expressing the Behavior of parts of a system …, state machines can also be used to express the valid interaction sequences, called protocols, for parts of a system. These two kinds of StateMachines are referred to as behavior state machines and protocol state machines respectively.”
MODAF specifies both node and activity, DODAF says activity only:
Short Name DODAF DODAF MODAF/NAF MODAF/NAF
OV-6b OV-6b State Transition Description DoDAF: The Operational State Transition Description (OV-6b) DoDAF-described View is a graphical method of describing how an Operational Activity responds to various events by changing its state. The diagram represents the sets of events to which the Architecture will respond (by taking an action to move to a new state) as a function of its current state. Each transition specifies an event and an action. OV-6b Operational State Transition Description MODAF: OV-6b: The Operational State Transition Description is a graphical method of describing how an Operational Node or activity responds to various events by changing its state. The diagram represents the sets of events to which the Architecture will respond (by taking an action to move to a new state) as a function of its current state. Each transition specifies an event and an action.
UPDM states node only?