Education Policy and Comparative Education” by Mark Bray and Bob Adamson – Link

Recently, there have been many different web service policy language proposals withvarying degrees of expressivity and complexity [21,6,1]. One of these languages, WS-Policy became a W3C member submission and is the basis for the WS-Policy workinggroup3.In previous work [13] we described a translation of WS-Policy to a standardizedlogic (OWL-DL). This mapping essentially provided a formal semantics for the frame-work, and allowed us to use an OWL DL reasoner for policy processing tasks such asdetermining policy equivalence, incompatibility, containment, incoherence and expla-nation. In this paper, we provide additional results on the translation by exploring theoperation of policy intersection. This operation determines whether two policies arecompatible and generally involves domain-specific processing. In the official specifica-tion of WS-Policy [21], only an approximation algorithm is defined for this operation.Instead, we describe an algorithm based on OWL-DL extended with default rules. Be-cause default logic is computationally more expensive than the logic behind OWL-DL,we do provide clear motivations for our usage of defaults.