Setting optional number of Web services in Web service communities based on queue theory

Users always wait to be served by Web service in the community. The cost of Web service community is increased due to the users queue up in the community will consumes resources. In this paper we research on setting optional number of Web services in the community in order to make the cost of community be minimum. A solution was proposed based on both theory of queue and marginal analysis method. The queue model in the Web service community is M/M/n. In the M/M/n model, we combine the theory of queue to calculate the length of users in the community when the queue is in stable condition. Then we find out the cost function based on the cost factors of Web service community. The optional number of Web service is found after the community cost is counted based on the cost function and analyzing in marginal analysis theory. Our solution is proved to be effective to find out proper number of Web service in the community after the experiment.