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- | ====== Fact Space Model ====== | ||
- | The Fact Space model is a coordination model which provides applications with a //federated fact space//: a distributed knowledge base containing logic facts which are implicitly made available for all devices within reach. | ||
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- | To react to the appearance of facts in the federated fact space, applications specify //logic rules// | ||
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- | In summary, the Fact Space model combines the notion of a federated fact space with a logic coordination language. In the remainder of this section we will discuss each of these components in slightly more detail. | ||
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- | ===== Federated Fact Space ===== | ||
- | The Fact Space model equips every application with a private fact space in which application-specific facts can be stored. | ||
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- | In essence, the distribution semantics of the federated fact space in the Fact Space model are largely similar to those of the federated tuple space of [[http:// | ||
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- | The fact that applications can respond to both the assertion and the retraction of facts is of particular importance when devices go in and out of earshot. For instance, when a new device is discovered, its interface fact space will be // | ||
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- | ===== Logic Coordination Language ===== | ||
- | The Fact Space model provides applications with a logic coordination language to cherry pick the relevant context | ||
- | information from the federated fact space. | ||
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- | < | ||
- | preference(meetingRoom, | ||
- | preference(office, | ||
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- | : | ||
- | location -> detected(myID, | ||
- | preference(? | ||
- | </ | ||
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- | Subsequently, | ||
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- | Applications can supply application-level actions (such as '': | ||
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- | ===== Further Reading ===== | ||
- | S. Mostinckx, C. Scholliers, E. Philips, C. Herzeel, W. De Meuter. **Fact Spaces: Coordination in the Face of Disconnection.** In Murphy and Vitek (eds.), //Proc. of the 9th Int. Conf. on Coordination Models and Languages (COORDINATION)// |