Découverte d'annuaires de services web dans un environnement distribué. (Web services registries discovery in a distributed environment)

Web services can be seen as a pillar block for achieving electronic B2B transactions. More and more companies are using Web services to achieve transactions with their partners and/or offer on-line services. These companies have to make their Web services available for consultation through their own private Web service registries. As a result, the number of Web service registries that are made available for use can be as many as the large number of companies. This raises an old, search engine, problem in a new form : discovery mechanisms of Web services are not efficient both in response times and quality of results. Basically, a company interested in a service has to screen several registries to discover the service that best suits its needs. This task can be very cumbersome since the number of available registries, and also the services they advertise can be very large. In this context, if appropriate solutions are not considered, "traditional" Web services discovery mechanisms that consist of scanning all the registries would for instance slow down the increase rate of Web services. In this thesis, we are interested in Web services discovery in a distributed registry environment. To do this, we first propose to organize a registries network into communities based on functionalities offered by the Web services of a registry. Then, to handle the dynamic nature of communities and their members, we define the needed management mechanisms to monitor changes and reconcile potential conflicts. We identify the different capabilities of a registry (joining a community, updating functionalities,...) and a community (creation, dismantling, merging,...) life-cycle and we specify the associated management operations. Finally, we propose an approach for Web services registries discovery that uses two filters to limit the search space. We first use the functional requirement of a service requester to select the appropriate registry community. Then we use the requester’s non-functional requirements and his behavior to select the registries. The proposed solutions were tested by setting up a P2P network of registry communities, implementing a community manager and a discovery system.