Scalable Orchestration Strategy for Automatic Service Composition

The goal of Automatic Service Composition (ASC) is to create value-added services automatically from existing services. Most research into service composition is based on four stages (planning, discovery, selection, and execution) and their variations, and do not consider nested dynamic services where ASC calls inner ASCs internally during composition. In practice, there are many situations where dynamic services and existing services are combined in ASC. This research proposes a strategy for orchestrating the existing four-staged composition and nested dynamic service composition. Two approaches are considered: top-down and bottom-up. Top-down composition can create new services with management using a main composer, while bottom-up composition creates a new service under human-oriented direction. For the two proposed solutions, core procedures are described, and prototype systems are implemented in one domain. Finally, the performance of top-down composition is evaluated.