Independent Global Constraints Web Service Composition Optimization Based on Color Petri Net

Under the service-oriented circumstances, developers can rapidly create applications through Web service composition, but the wholly intellectualized automatic composition is a very complicated process. So, many applications and research about composite services emphasize on semi-automatic mode. This paper presents independent global constrains-aware Web service composition method based on color Petri net (CPN) and genetic algorithm (GA). Firstly, a CPN modeling methods which can describe multi-attribute multi-constraint relations and associate relation between component services is proposed. Secondly, combining with the properties of CPN, GA is used to search a legal firing sequence in the CPN model, and the composite service corresponding to the legal firing sequence. Using legal firing sequences of the Petri net makes the service composition locating space based on GA shrink greatly. Theoretical analysis and experimental results indicate that this method owns both lower computation cost and higher success ratio of service composition.