Abstract: With the high development of Web services technology, there are several features similar Web service on Internet. How to select suitable services to meet the needs of customers and generate the service composition has become one of the major issues. Based on the existing QoS service selection method is usually assumed that service provider's value is real and fixed, but the duality of services often changes in the actual operation. Therefore, the paper put forward a dynamic change of data to consider QoS service selection method. The method introduces a reliable QoS sulrperiods,which can be more relevant to describe the actual operation of service. The method according to service at different time changes on the reliability of the subdivided into different services, using redundant, under a different time period to meet the requirements to provide users with multiple options for services. Finally, a simulation experiment shows the availability and effectiveness of the method.

Key words: Service selection algorithm, Reliable model of timesharing, Service set pretreatment