Personae: um modelo de mediação semântica para arquiteturas orientadas a serviços.

Abstract

Nowadays, personalization is a strong trend in service provisioning. This trend can also be noticed on the Web, where some degree of automation in processes such as information discovery and selection points to a concern on differentiated services provisioning. However, clients and providers do not share the same perspective about the same service very often. These perspectives diverge through two dimensions: interest conflicts and how these interests can be represented. Ontologies are shared vocabularies used to define different knowledge domains on the Web. Nevertheless, it is unrealistic to expect a global consensus between people and organizations onto a common, shared ontology. Therefore, the need of a mediationcentered approach for reconciliation of these different vocabularies becomes clear, in order to close the gap between the sides involved towards a better communication. This implies the inclusion of a mediator between them, in order to identify similarities on the vocabularies used. The transparency in this process brings benefits to both of them. On the client side, it can be essential in allowing discovery and selection of the most appropriate services. On the provider side, the meaning of the “standard” can be just one more “option”. It brings the possibility of communication despite the differences. To deal with this aspect, this master degree thesis defines a mediation model for Service Oriented Architectures, named PERSONÆ, based on ontology reconciliation. Differently from traditional approaches, PERSONÆ represents a formal model for describing behavioral aspects of the mediator for this context, in a precisely and unambiguously manner. This model provided a deep understanding about ontology reconciliation techniques like merging, integration and alignment, making clear how these can be combined in order to minimize semantic heterogeneity problems, more specifically in service discovery, service selection and service level agreements establishment on the Web.