Context Aware Service Policy Orchestration

While service oriented computing is gaining popularity and design methodology for functional features is becoming mature, design of non-functional features and governance capabilities is increasingly important. WS-policy has been touted as a standard way to specify service policy for these features and map service policy to upper layers of SOA policy model for SOA governance. This paper introduces a novel model-driven method to orchestrate service policy within system context in design time. By applying top-down SOA design methodology, firstly the logical service policy model is created to describe relation among service policy in logical level, and then it is transformed to physical service policy model with more factors of real system topology considered. Finally, service policy deployment model is generated to describe the relation among policy related artifacts and policy repositories, and guide and automate the deployment of policies in runtime environment as well. Leveraging system topology and behavior information, service policies are orchestrated vertically and horizontally according to service policy dependency, business policy, service level agreement (SLA), and domain specific constraints. Meta-policy based service policy conflict detection and resolution is highlighted. We demonstrate how this approach significantly enhances the capability to ensure the correctness and consistency of service policy within service oriented computing environment.