We present a new and powerful class of automata which are explicitly concurrent and allow a very simple definition of composition. Time synchrony is obtained by using a global clock. Message asynchrony is obtained by requiring the automata to react to every input.
Explicit concurrency is obtained by marking each transition with a set of input and output messages.
We compare these automata with a history based approach which uses the same communication mechanism and show that they are equivalent. We present a new and powerful class of automata which are explicitly concurrent and allow a very simple definition of composition. Time synchrony is obtained by using a global clock. Message asynchrony is obtained by requiring the automata to react to every input. Explicit concurrency is obtained by marking each transition with a set of input and output messages.