Research On Web Services Discovery Based On QoS And User Preference

The application of web services is based on the web services discovery, which guarantees integration and sharing of web resources. As the establishment of technological standards of web services and the maturation of application platforms supporting web services, the amount of web services published on the Internet has increased in geometric growth. How to discover and choose a proper web service according to user preference needs to be discussed.The services discovery methodology based on UDDI is in short of the description of the information of QoS and lower efficiency. The services discovery methodology based on semantic deduction is not convenient to implemented and with lower practicability. Web services discovery based on QoS is the precondition of designing function and choosing the best services. Different user has their own preference of web services discovery in different situation. To discover services based on QOS and user preference can improve the application level of web services.A model of web services discovery based on QoS and use preference is proposed in the thesis. The model takes the user's QoS constraint as the choosing standard. The related technology of web services discovery is discussed in detail, including the system architecture of web services, technical manual, the mechanism of services discovery, the description language of services and the assorting of services discovery. The framework of the model is designed in the thesis. The process of implementation of the model is analyzed in detail which includes the roles in the model with its function, setting the QoS monitor to control the change of QoS information while adapting the information automatically, the algorithm of web services discovery based on the user preference. The prototype of the system is implemented in the environment of.NET. The discovery based on user preference is described in this thesis, including the basic discovery, partial order of QoS attribute, combing the design and implementation process of QoS and the monitor of QoS. The publish and discovery function of the prototype is described in detail. The running result of the prototype is analyzed. The prototype is proved be able to discover the proper web services based on user preference with higher accuracy rate compared with the services discovery method used in UDDI.