Summary: Dynamic Input/Output Automata: a Formal
Model for Dynamic Systems
Paul C. Attie 1 2 and Nancy A. Lynch 2
1 College of Computer Science, Northeastern University, Cullinane Hall,
360 Huntington Avenue, Boston, Massachusetts 02115.
2 MIT Laboratory for Computer Science, 545 Technology Square,
Cambridge, MA, 02139, USA.
Abstract. We present a mathematical state-machine model, the Dy-
namic I/O Automaton (DIOA) model , for dening and analyzing dy-
namic systems of interacting components. The systems we consider are
dynamic in two senses: (1) components can be created and destroyed
as computation proceeds, and (2) the events in which the components
may participate may change. The new model admits a notion of external
system behavior , based on sets of traces. It also features a parallel com-
position operator for dynamic systems, which respects external behavior,
and a notion of simulation from one dynamic system to another, which
can be used to prove that one system implements the other.