A method for dynamic QoS-aware Web services selection

In order to deal with the QoS(Quality of Services)value fluctuations of Web services in dynamic environment, a service selection method based on dynamic QoS is proposed. Firstly, the method establishes an interval QoS model to represent the dynamic changes of QoS values. Then it uses the interval similarities to measure the proximity of the QoS values provided by candidate services to the QoS requirement values provided by consumers. Based on the concept of similarity, the objective weight of QoS attribute for each basic service is calculated using TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)method for MADM(Multiple Attribute Decision Making)problems. After calculating the comprehensive weight by combining with the consumers' subjective preference, recommendations are used to sort the candidate services. The experimental results show that this service selection method not only considers the consumers' subjective preference, but also overcomes the impact of fluctuations in QoS values of Web services, and enhances the correctness of service selection.