Web Services for the Integration of XML-Based Content into Learning Platforms: A Three-level Model

Along with the increasing diversity of educational markup languages there is a strong need for flexible integration of such content into learning platforms. Therefore, we have identified four basic mechanisms: plain linking from the platform to external content, conversion of content into the platforms native format, and service-based invocation of external content as well as specific functionality related to it. Architectural principles, benefits, and drawbacks of these concepts are compared, and exemplary realizations are described.