UMBC ebiquity

An architecture for enterprise information interoperability

Speaker: David Wood

Start: Friday, November 09, 2012, 11:00AM

End: Friday, November 09, 2012, 12:15PM

Location: 325b ITE, UMBC


The World Wide Web differed from other early hypertext systems in the removal of "back links" (the ability of a hyperlinked object to link back to a referring resource). The removal of back links allowed the scalability inherent in the Web's design, but sacrificed the knowledge necessary to update links when content moved. Persistent URLs (PURLs) have been used on the Web since 1995 to provide an inexpensive and partial solution to link updates via HTTP redirection: PURLs do not change their URL, but they may change the target they redirect to. Various iterations of the PURL concept have allowed Web addresses to be updated, clients notified of permanent changes of address and the provision of directions to metadata about a requested resource.

"Active" PURLs are a relatively new (2007) iteration of the PURL concept that allow PURLs to actively participate in the creation of data returned. The Callimachus Project, an Open Source Linked Data management system, now implements Active PURLs as a means to automate the collection, transformation and provision of information from distributed sources. Active PURLs are implemented in Callimachus by means of a PURL service, a new PURL type and an XML pipeline (XProc) implementation.

This talk will introduce Active PURLs and describe how they may be used to address long standing problems in enterprise architecture, especially those of distributed information interoperability, by facilitating a strong separation of concerns between data producers, publishers, administrators, librarians and consumers.

Dr. David Wood has contributed to the evolution of the World Wide Web since 1999, especially in the formation of standards and technologies for the Semantic Web. He has architected key aspects of the Web to include the Persistent Uniform Resource Locator (PURL) service and several Semantic Web databases and frameworks. David is co-chair of the W3C RDF Working Group, co-chaired the Semantic Web Best Practices and Deployment Working Group and is a member of the Semantic Web Coordination Group. David has represented international organizations in the evolution of Internet standards at the International Standards Organization (ISO), the Internet Engineering Task Force (IETF) and the World Wide Web Consortium. David is a founding and contributing member of many Free/Libre/Open Source Software (FLOSS) projects, including the Mulgara Semantic Store, Persistent URL (PURLs), Freemix and the Callimachus Project. He is the author of Programming Internet Email (O'Reilly, 1999), editor of Linking Enterprise Data (Springer, 2010) and Linking Government Data (Springer, 2011) and lead author of Linked Data (Manning, anticipated 2013).

Host: Tim FInin,

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Tags: semantic web, purl

Host: Tim Finin