Research On The Method Of Web Services Composition For User’s Privacy Requirement

As the development of Service-oriented Architecture(SOC), Web services composition has been applied in various fields of daily life. When using Web services composition, consumers have to submit some personal private information to support the execution of necessary business process. So, on the premise of meet the needs of business, how to find one Web services path which meet the users’ privacy requirement become a research focus in the field of service computing.Existing method of Web services composition is more concerned about how to meet the user’s business needs. Even if the privacy requirement is concerned, it only solute the privacy requirement that is relatively simple. The features of environment of Web service is dynamic, heterogeneous and autonomous, that makes privacy protection must consider interactions between services, must limit the dependencies between the user’s privacy data.At the same time, the features make most of dependency between the privacy data showing a temporal feature. Because of model checking can verification the temporal characteristics of the system in the field of computer technology, this paper presents a method to find one Web services composition which meets the user’s privacy requirement by using model checking tools. The major work is listed as follow:Firstly, due to some dependencies among privacy data can be expressed by temporal properties, so the use of linear temporal logic to describe the dependencies between private data in the requirement. First needing to classify the dependency between privacy data and analyse the correspondence between temporal dependency of privacy data and behavior restriction of Web services, the idea of extracting linear temporal logic specification from the temporal properties of privacy requirement is put forward.Secondly, taking into account the input order of the model checking tools, after completing the description of the privacy requirment by LTL, an approach for modeling the privacy behaviors of Web services composition by privacy activity diagram is proposed, including the transformation from BPEL activities to privacy activity diagram. Then, the activity diagrams are transformed to Promela description, the input language of model checker SPIN.Finally, a prototype tool is designed and implemented to conduct privacy modeling for WS-BPEL and achieve data dependency. Analysing the result verification of privacy requirement by SPIN to find one Web services composition path. Besides, the effectiveness of the proposed method is demonstrated through a case study.