A Petri-net Coverability Model for Automatic Web Service Composition

Web services are widely used because of their features of interoperability, loose-coupled and platform independent. Web services composition is one of the hottest topics in service computing area. In this paper a method based on Petri net coverability problem is proposed to handle automatic service composition. First each service is translated into component of Petri net and the input/output places with same semantics are merged. According to user’s input and desired output, the initial marking and target marking can be obtained. Then the coverability tree and coverability graph can be constructed. At last the node on the coverability graph which can cover the target marking should be find out, and shortest coverability path translated into smallest service executing sequence to reach the goal of automatic service composition.