Alternating-Time Stream Logic for Multi-agent Systems

Constraint automata have been introduced to provide a compositional, operational semantics for the exogenous coordination language Reo, but they can also serve interface specification for components and an operational model for other coordination languages. Constraint automata have been used as basis for equivalence checking and model checking temporal logical properties. The main contribution of this paper is to reason about the local view and interaction and cooperation facilities of individual components or coalitions of components by means of a multi-player semantics for constraint automata. We introduce a temporal logic framework that combines classical features of alternating-time logic (

${\it ATL}$

) for concurrent games with special operators to specify the observable data flow at the I/O-ports of components. Since constraint automata support any kind of synchronous and asynchronous peer-to-peer communication, the resulting game structure is non-standard and requires a series of nontrivial adaptations of the

${\it ATL}$

model checking algorithm.