Date Added: Apr 2012
Very large scale systems of autonomous concurrent objects (Actors) require coordination models to meet two competing goals. On the one hand, the coordination models must allow Actors to dynamically modify protocols in order to adapt to requirement changes over the, likely extensive, lifetime of the system. On the other hand, the coordination models must enforce protocols on potentially uncooperative Actors, while preventing deadlocks caused by malicious or faulty Actors. To meet these competing requirements, the authors introduce a novel, scoped semantics for Synchronizers a coordination model based on declarative synchronization constraints.