QoS-Aware Web Services Discovery with Federated Support for UDDI

Abstract

Web services’ discovery mechanism is one of the most important research areas in Web services because of the dynamic nature of Web services. In practice, UDDI takes an important role in service discovery since it is an online registry standard to facilitate the discovery of business partners and services. However, QoS related information is not naturally supported in UDDI. Service requesters can only choose good performance Web services by manual test and comparison. In addition, discovery among private UDDI registries in a federation is not naturally supported. To address these problems, we propose UDDI extension (UX), an enhancement for UDDI that facilitates requesters to discover services with QoS awareness. In this system the service requester invokes and generates feedback reports, which are received and stored in local domain’s UX server for future usage. By sharing these experiences from those requesters in the local domain, the UX server summarizes and predicts the service’s performance. A general federated service is designed to manage the service federation. The discovery between different cooperating domains is based on this general federated service, and therefore the links between domains are maintained dynamically. The system handles the federated inquiry, predicates the QoS difference among different domains, and provides a simple view over the whole federation. Meanwhile, the UX server’s inquiry interface still conforms to the UDDI specification.