Piergiorgio Bertoli, Marco Pistore, Paolo Traverso
Composition of stateful web services expressed in BPEL4WS can be recasted as a problem of planning in asynchronous domains. In (PTB05), this is pursued by encoding the asynchronous and partially observable behaviors of services within a domain whose states represent 'beliefs' on the state of each service. In this work, we propose a novel approach, where such belief-level domain is not built explicitly, but rather visited on-the-fly. We evaluate the relative merits of the approaches, showing the advantages of the on-the-fly approach for a significant class of composition problems.