Study On Verification Method For Web Service Compositional Compatibility Based On Pi-Calculus

As a new distributed computing model, one of web service goals is to construct a universal, platform-indepentdent, language-indepentdent technical layer over existed heterogeneous platforms. With this layer, the connection and integration can be easily achieved among different applications over heterogeneous platforms. However, how to web service come into practical period and to realize inter-organizational and cross-domain system integrating and automatic interaction still face a series of problems. Due to lack of correct verification, many web service compositions can not ensure that internal process structure is correct or not, that services of composition whether exist dead locks and live locks, that validation of behavior compatibility is carried out or not, and so on. Using the formalized language - pi-calculus, this thesis studies verification method for web service compositional compatibility.Firstly, based on practical situations, this thesis analyses the research situations and results at home and abroad, discusses the necessities of verification of web service composition, and determines verification method being adopted. After a brief introduction to the basic theory and correlative technology of web service and web service composition, this thesis makes a further research on the grammatical definition, the structure equivalent rules, the operational semantics and behavioural equivalence of pi-calculus, and mainly studies the related concepts of compatibility and the descriptions of the interactive behaviors between web services. And then according to the established model, this paper verifies the behavior compatibility of web service using pi-calculus, and puts forward the verification method of web service composition based on pi-calculus. Finally, this paper completes the verification process by MWB.Verification of web service composition can pre-find existing defects in web service composition. It is a key to improve success rate of web service compositional execution and to enhance the user satisfaction degree, and it has very important significance to correct operation of web service composition and monitoring.