Named Graphs, Provenance and Trust Jeremy J. Carroll Christian Bizer Hewlett-Packard Labs Freie Universitat¨ Berlin Bristol, UK Germany
[email protected] [email protected] Pat Hayes Patrick Stickler IHMC, Florida, USA Nokia, Finland
[email protected] [email protected] ABSTRACT privacy preferences to graphs in order to restrict the usage of The Semantic Web consists of many RDF graphs nameable by published information [18, 34]. URIs. This paper extends the syntax and semantics of RDF to cover Access control A triple store may wish to allow fine-grain access such Named Graphs. This enables RDF statements that describe control, which appears as metadata concerning the graphs in graphs, which is beneficial in many Semantic Web application ar- the store [28]. eas. As a case study, we explore the application area of Semantic Signing RDF graphs As discussed in [13], it is necessary to keep Web publishing: Named Graphs allow publishers to communicate the graph that has been signed distinct from the signature, assertional intent, and to sign their graphs; information consumers and other metadata concerning the signing, which may be can evaluate specific graphs using task-specific trust policies, and kept in a second graph. act on information from those Named Graphs that they accept. Stating propositional attitudes such as modalities and beliefs [27]. Graphs are trusted depending on: their content; information about Scoping assertions and logic where logical relationships between the graph; and the task the user is performing. The extension of graphs have to be captured [6, 25, 31]. RDF to Named Graphs provides a formally defined framework to Ontology versioning and evolution OWL [19] provides various be a foundation for the Semantic Web trust layer.