AWSP: An Automatic Web Service Planner Based on Heuristic State Space Search

With the number of available Web services is rapidly increasing, how to compose multiple Web services automatically to fulfill a given request has attracted much attention. This paper proposes a dedicated planner named AWSP (Automatic Web Service Planner) toward this problem. Compared with other AI planners for automatic Web service composition, AWSP is characterized by its two different heuristic functions to reduce the search space greatly. A series of experiments based on test sets generated by WSBen show that 1) AWSP performs well even when the scale of the test set expands significantly. 2) AWSP has a smaller search space and performs better when using the backward search strategy than using the forward search strategy, 3) AWSP with the A* heuristic function can get the solution with the shortest invocation path.