XrML-RBLicensing approach adapted to the BPEL process of composite web services

Web service orchestration represents an open and standards-based approach for connecting web services together leading to higher level of business processes. Business Process Execution Language (BPEL) engines are designed to handle this orchestration. However, web service compositions into BPEL suffer from several non-functional requirements such as security. To address this problem, we propose in this paper a novel approach that is based on a harmony between the licensing concept offered by eXtensible rights Markup Language (XrML), aspect-oriented programming (AOP), and web service compositions in BPEL. Our proposed approach, based on XrML, offers the ability to associate security licenses with activities offered by the composite web services. It allows to automatically generate BPEL aspects depending on the developed licenses, to separate between crosscutting concerns of the composed web services, and provides an easy way to include and update the non-functional requirements (e.g., security) into a BPEL process. It offers also the ability to validate the licenses, at runtime and without affecting the business logic of this model. To evaluate our approach, we have developed an inventory control system (ICS) sample that is composed of several web services. Case study and performance analysis are presented to demonstrate its feasibility as well.