Approaches to implementing active semantics with XML schema

In order to enrich XML with event driven, active behavior, the Active XML Schema approach defines active behavior within XML schemas along metadata, and stores traces of active behavior such as occurred events within XML documents along data. The semantic expressiveness of XML Schema, the schema language recommended by the W3C, however, is not sufficient to define the active semantics of Active XML Schema concepts. The contribution of this paper is to identify, explore, and evaluate approaches to implementing Active XML Schema with XML Schema, discussing the trade-off between semantic expressiveness and interoperability. Assuming that Active XML Schema may be seen as representative for tailored schema languages, the findings of this paper can be applied for arbitrary tailored schema languages.