Network Working Group J. Borden Request for Comments: 00 St. Vincent Health System Category: Informational November 2002 application/owl+xml Media Type Registration Status of this Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract This document describes a media type (application/owl+xml) for use with the RDF/XML serialization of the Web Ontology Language (OWL). OWL is intended to provide a language that can be used to describe the classes and relations between them that are inherent in Web documents and applications. Borden Informational [Page 1] RFC 00 application/owl+xml November 2002 Table of Contents 1. Discussion of this Document . . . . . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. application/owl+xml Registration . . . . . . . . . . . . . . . . 4 4. Social Context . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. Fragment Identifiers . . . . . . . . . . . . . . . . . . . . . . 6 6. Entailment parameter . . . . . . . . . . . . . . . . . . . . . . 6 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 7 References . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 Full Copyright Statement . . . . . . . . . . . . . . . . . . . . 9 Borden Informational [Page 2] RFC 00 application/owl+xml November 2002 1. Discussion of this Document Please send comments to . To subscribe, send a message with the body 'subscribe' to . The mailing list is publically archived at . 2. Introduction The Web Ontology Language (OWL) is intended to provide a language that can be used to describe the classes and relations between them that are inherent in Web documents and applications. The interchange language for OWL is the RDF/XML syntax [4] as described in the OWL Reference [1]. An OWL document may be served with the application/rdf+xml media type in which case the document is interpreted according to the application/rdf+xml media type [3] registration. An OWL document may be served with the application/ owl+xml media type in which case it is interpreted according to the value of the entailment parameter. The value of the entailment parameter is a URI which references a model theory or other formal definition of which entailments are intended by the author or server of the document to be licensed by the client of the document. simple: the document is interpreted as simple RDF according to the RDF model theory. The URIref for simple RDF entailments is http:/ /www.w3.org/TR/rdf-mt/#entail RDFS: the document is interpreted as RDF Schema according to the RDF model theory. The URIref for RDFS entailments is http:// www.w3.org/TR/rdf-mt/#rdfs_interp lite: the document is interpreted as OWL according to the OWL direct semantics. It conforms to the OWL Lite syntax. The URIref for OWL Lite entailments is @@OWL Lite MT [10] DL: the document is interpreted as OWL according to the OWL DL semantics. It conforms to OWL DL. The URIref for OWL DL entailments is http://www.w3.org/TR/owl-semantics/direct.html full (default): the document is interpreted as OWL according to the OWL/RDF semantics. It conforms to OWL Full. The URIref for OWL Full entailments is http://www.w3.org/TR/owl-semantics/ rdfs.html#5.4 When an OWL document is served with the application/xml media type, no particular interpretation is indicated and must be arranged by Borden Informational [Page 3] RFC 00 application/owl+xml November 2002 private agreement between publisher and consumer of the document. Application/xml might be used when the document is intended to be an example. The OWL model theory licenses additional entialments from the RDF model theory interpretation of the same RDF/XML document. Such differences between these interpretations are discussed in the OWL model theory document. 3. application/owl+xml Registration This is a media type registration as defined in Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures [8] MIME media type name: application MIME subtype name: owl+xml Required parameters: none Optional parameter: charset Same as charset parameter of application/xml. Encoding considerations: Same as charset parameter of application/xml. Optional parameter: entailment http://www.w3.org/TR/rdf-mt/#entail: simple RDF entailments apply. http://www.w3.org/TR/rdf-mt/#rdfs_interp: RDFS entailments apply. @@OWL Lite: OWL Lite syntax and entailments apply. http://www.w3.org/TR/owl-semantics/direct.html: OWL DL syntax and entailments apply. http://www.w3.org/TR/owl-semantics/rdfs.html#5.4 (default): OWL Full syntax and entailments apply. Security considerations: Security considerations include many of those described in section 10 of RFC 3023 [6] as well as those described in the application/rdf+xml media type registration [3]. Borden Informational [Page 4] RFC 00 application/owl+xml November 2002 Interoperability considerations: Published specification: see Web Ontology Language (OWL) 1.0 Reference [1] and OWL Abstract Syntax and Semantics [2] (working drafts as of 2002-11) Applications which use this media type: OWL is device-, platform-, and vendor-neutral and is supported by a range of Web Ontology user agents, authoring tools and inferencing engines. Additional information: Magic number(s): none Although no byte sequences can be counted on to consistently identify OWL, RDF documents will have the sequence "http:// www.w3.org/1999/02/22-rdf-syntax-ns#" to identify the RDF namespace. This will usually be towards the top of the document. OWL documents may or may not declare the OWL namespace "http://www.w3.org/2002/07/owl#" File extension(s): .owl,.rdf Macintosh File Type Code(s): "TEXT" For further information: Jonathan Borden RDF Logic More information may be found on the WebOnt website: Intended usage: COMMON Author/Change controller: The OWL specification is a work product of the World Wide Web Consortium. The W3C and the W3C WebOnt Working Group have change control over the specification. Borden Informational [Page 5] RFC 00 application/owl+xml November 2002 4. Social Context @@ 5. Fragment Identifiers application/owl+rdf uses the same fragment identifer syntax and semantics as application/rdf+xml. The rdf:ID and rdf:about attributes can be used to define fragments in an RDF document. Section 4.1 of the URI specification [7] notes that the semantics of a fragment identifier (part of a URI after a "#") is a property of the data resulting from a retrieval action, and that the format and interpretation of fragment identifiers is dependent on the media type of the retrieval result. 6. Entailment parameter The optional entailment parameter is used to indicate which entailments are licensed by the publisher of the document to be derived from the assertions made in the document. http://www.w3.org/TR/rdf-mt/#entail: simple RDF entailments are licensed. Example use of this parameter as part of an HTTP GET operation: Accept: application/owl+rdf; entailment="http://www.w3.org/TR/ rdf-mt/#entail" , application/rdf+xml http://www.w3.org/TR/rdf-mt/#rdfs_interp: entailments as per RDF Schema are licensed. Example use of this parameter as part of an HTTP GET operation: Accept: application/owl+rdf; entailment="http://www.w3.org/TR/ rdf-mt/#rdfs_interp" @@OWL Lite: entailments as per OWL DL are licensed. The syntax is intended to conform to OWL Lite. Example use of this parameter as part of an HTTP GET operation: Accept: application/owl+rdf; entailment="@@OWL Lite" http://www.w3.org/TR/owl-semantics/direct.html: entailments as per Borden Informational [Page 6] RFC 00 application/owl+xml November 2002 OWL DL are licensed. Example use of this parameter as part of an HTTP GET operation: Accept: application/owl+rdf; entailment="http://www.w3.org/TR/ owl-semantics/direct.html" http://www.w3.org/TR/owl-semantics/rdfs.html#5.4: entailments as per OWL Full are licensed. Example use of this parameter as part of an HTTP GET operation: Accept: application/owl+rdf; entailment="http://www.w3.org/TR/ owl-semantics/rdfs.html#5.4" This value is the default if none is specified. 7. IANA Considerations This document calls for registration of a new MIME content-type, according to the registration template in section 2. 8. Acknowledgements @@ References [1] Dean, M., "Web Ontology Language (OWL) 1.0 Reference", W3C owl- reference, July 2002, . [2] Patel-Schneider, P., "Web Ontology Language (OWL) 1.0 Abstract Syntax and Semantics", W3C owl-reference, November 2002, . [3] Swartz, A., "application/rdf+xml media type Registration", IETF rdf-xml-media-type, August 2002, . [4] Beckett, D., "RDF/XML Syntax Specification (Revised)", W3C rdf- syntax-grammar, March 2002, . [5] Hayes, P., "RDF Model Theory", W3C rdf-mt, April 2002, . [6] Murata, M., St. Laurent, S. and D. Kohn, "XML Media Types", RFC Borden Informational [Page 7] RFC 00 application/owl+xml November 2002 3023, January 2001. [7] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform Resource Identifiers (URI): Generic Syntax", RFC 2396, August 1998. [8] Freed, N., Klensin, J. and J. Postel, "Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures", BCP 13, RFC 2048, November 1996. [9] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [10] <> Author's Address Jonathan Borden St. Vincent Health System Section of Neurosurgery 311 W. 24th Street Erie, PA 16502 USA Phone: +1 814 455 4868 EMail: jonathan@openhealth.org URI: http://www.openhealth.org/ Borden Informational [Page 8] RFC 00 application/owl+xml November 2002 Full Copyright Statement Copyright (C) The Internet Society (2002). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Acknowledgement Funding for the RFC Editor function is currently provided by the Internet Society. Borden Informational [Page 9]