This behavior is distributed in that different FSMs do different tasks. The total behavior of the architecture is nearly approximated by the sums of the component FSMs.
Subsumption Architecture is parallel and asynchronous because the AFSMs operate independently of each other. All AFSMs are always running, and while they may have their own timers, they need not explicitly synchronize with each other in the sense that clocked digital circuits do.
Subsumption Architecture can be characterized as interruptible because it is always pays keen attention to its sensory readings and acts accordingly. But this label is misleading. Interruptibility classically means the ability to stop what ones doing to attend to a condition (often an environmental condition). But Subsumption Architecture always attends to its inputs . . . there is no effort independent of them. Thus, Subsumption Architecture may be better characterized as always interrupting a null action.
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