Service Supervision for Runtime Service Management

Abstract

The Language Grid offers language services with a standardized interface and different non-functional properties. This allows us to create a specialized composite service for our own goals simply by selecting the appropriate services. The language services are, however, provided in various formats with their own policies. In an environment for service-collective intelligence, it is essential to have many service providers join by strongly ensuring that their policies are satisfied. In doing this, we therefore we have to solve the following problems. First, service composition relies on the products of various stakeholders that belong to different organizations, such as service products and composite service designers. This makes it difficult to modify existing services in line with given requirements. Next, selection of services may impose constraints on execution. We therefore often need to apply a certain amount of runtime adaptation toward a composite service in order to enforce given policies. To solve these problems, we proposed an architecture for runtime service management called Service Supervision. Service Supervision provides meta-level execution functions for composite services. These allow operators to modify behaviors of a composite service without changing its model. Service Supervision is also capable of effectively managing a comprehensive process of runtime service selection and adaptation in order to ensure the service providers’ policies are satisfied. We implemented the Service Supervision prototype and showed that applying meta-level execution control barely decreases performance.