NOTE: These slides have not been updated since 2003. They have been superseded by the book An Introduction to XML and Web Technologies Addison-Wesley, and the accompanying online material. Please see http://www.brics.dk/ixwt/ for more information. Anders Møller and Michael Schwartzbach, February 2006

THE XML REVOLUTION  -  TECHNOLOGIES FOR THE FUTURE WEB

Problems with HTML links

Construction of a hyperlink:

• <a name="here"> is placed at the destination
• <a href="URL#here"> is placed at the source

Problems when using the HTML model for general XML:

• Link recognition:
  • in HTML, links are recognized by element names (a, img, ..)
    - we want a generic XML solution
  • the "semantics" of a link is defined in the HTML specification
    - we want to identify abstract semantic features, e.g. link actuation

• Limitations:
  • an anchor must be placed at every link destination (problem with read-only documents)
    - we want to express relative locations (XPointer!)
  • the link definition must be at the same location as the link source (outbound)
    - we want inbound and third-party links
  • only individual nodes can be linked to
    - we want links to whole tree fragments
  • a link always has one source and one destination
    - we want links with multiple sources and destinations

COPYRIGHT © 2000-2003 ANDERS MØLLER & MICHAEL I. SCHWARTZBACH