Name
Abstract | ||
|---|---|---|
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-y . We evaluate the relative merits of the approaches, showing the advantages of the on-the-y ap- proach for a signicant class of composition problems. search may identify a solution by visiting only a very small portion of the belief space, which is likely to reect in an improved composition performance. We propose a semi- symbolic and-or search approach that also deals with the existence of internal asynchronous service evolutions. This results in the rst instance ever of an and-or planning algo- rithm for nondeterministic, partially observable, and asyn- chronous domains. We compare this novel approach w.r.t. (PTB05), consid- ering differently structured composition scenarios. We show that the novel solution scales up of orders of magnitude for the cases where services to be composed have a certain amount of complexity. The paper is structured as follows. First, we dene the composition problem and provide a general schema for its solution. We then rephrase the problem in terms of belief- level search, and discuss our approach. Finally, we sketch our implementation, and report our experimental compari- son against the off-line approach of (PTB05). We wrap up discussing related work and future work directions. |
Year | Venue | Keywords |
|---|---|---|
2006 | ICAPS | web service |
Field | DocType | Citations |
Observable,Computer science,Theoretical computer science,Web modeling,Stateful firewall,Artificial intelligence,Asynchronous communication,World Wide Web,On the fly,Web service,Machine learning,WS-Policy,Encoding (memory) | Conference | 8 |
PageRank | References | Authors |
0.49 | 9 | 3 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Piergiorgio Bertoli | 1 | 775 | 46.89 |
| Marco Pistore | 2 | 3021 | 181.74 |
| Paolo Traverso | 3 | 3483 | 223.80 |