Modelling the Sharing of Resources across Collaborative Sessions

Service-oriented architectures can be used to provide multiple simultaneous sessions to users that wish to communicate over a variety of media. This gives rise to rich, highly effective communication sessions that can greatly enhance userspsila interaction. For example, a health services virtual organization seeks to use such tools for a variety of purposes: virtual patient simulation, anatomical visualization and virtually sharing cadaveric dissections. We propose SAVOIR, Service-oriented Architecture for Virtual Or- ganization Resource and Infrastructure for this task, where tools and applications are resources and they can be accessed and controlled via Web Services. The purpose of this paper is to present a method for modeling sessions in SAVOIR by using Web Ontology Language (OWL). We express in OWL 1.1 constraints on when sessions can and cannot be run or cannot be run concurrently with the ses- sions now running. There are several types of violations: aggregate bandwidth may exceed capacity, network infras- tructure may not be available, too many users may want to access a limited shared resource, etc. The session scheduler depends on the OWL 1.1 description logic reasoner to evaluate the session for violation of these constraints before the session is allowed to be scheduled.