An Automaton Interpretation of Message Sequence Charts

We give a precise semantics to Message Sequence Charts (MSCs), by interpreting MSC speci cations by B uchi automata. The state transition graph is uniquely determined by the speci cation, but di erent automata may be de ned to accept di erent sets of traces allowed by the speci cation. The precise automaton chosen therefore depends on reliability properties of communications assumed by the speci cation. CR