Web service provider selection under QoS and security constraints

In pervasive computing environment, Web services are widely adopted in dynamic business processes. When selecting service providers, quality of service (QoS) and security constraints should be considered simultaneously. However, most current research works about provider selection either focus on quality of service, or just take into account security constraints. In this paper, we propose an evaluation model for business process, which considers the above two factors at the same time. Two key criterias are introduced to measure the overall cost and benefit of QoS parameters respectively. Typical security constraints, such as separation of duty (SoD) constraints and binding of duty (BoD) constraints, are also considered. We define the service provider selection problem and present a linear programming based solution. Some experiments are performed to evaluate our model and the results show that our approach is effective in solving the problem.