A Model for Web Service Discovery with QoS Constraints
Sheng Yang · Chinese Journal of Computers · 2005
Quality of Service (QoS) describes the capabilities of a product or service to meet the requirements of consumers. The provision of guaranteed QoS is very critical to the success of web services in mission critical business domains. How to dynamically select web services that can best meet the requirements of consumers is an ongoing research direction in web service community. This paper proposes a model for web service discovery with QoS constraints called WSDM Q. A set of QoS categorization tModels and a kind of reputation categorization tModel are defined in the model to describe the QoS attributes of a service and the degree of guaranteed QoS delivered by a service respectively. The concept of quantification is introduced in the model to transform between the QoS attributes and QoS categorizations. Furthermore, a negotiation mechanism is used to allow admission control on the service provider side; a feedback mechanism is adopted to allow dynamic evaluation and adjustment of reputation of web services. Because of no need for changes in the inner implementation of UDDI service, it is easy to implement the model through the direct extension to the existing UDDI services. The authors have implemented a prototype based on Microsoft.Netf platform and Microsoft UDDI service.