A Conflict-Free Service Selection Algorithm in the Situation of Complex Service Dependency Relationships

Web service selection is a key step to construct a Web service composition system. For each system function, a suitable Web service must be selected from many candidate component services, respectively. However, when there exist complex dependency relationships between component services, it is difficult to make global service selections without any selection conflict. Therefore, we present a conflict-free service selection algorithm. First, a formal service selection model, which reflects the service composition process and the dependency relationships of component services, is presented. Then, a conflict-free service selection algorithm is designed, which can avoid and mediate selection conflicts by multilevel backtracking and service reselection. Finally, some simulation experiments are made to prove the validity and performance of the algorithm. By the presented algorithm, the global service selection process without any conflict can be accomplished successfully and rapidly.