A Novel QoS-Aware Service Composition Approach Based on Path Decomposition

QoS-aware Service Composition is to build new services by orchestrating a set of atomic services, and ensure the new services to satisfy certain QoS constraints. However, the current methods can´t be able to address the problem efficiently in the situation that the new service is comprised of multiple tasks, the structure of its execution path is complicated, and the number of corresponding candidate service is huge. Therefore, in this paper, a novel QoS-aware service composition approach based on path decomposition (SCP) is proposed, which adopts the Case-Based Reasoning and Genetic Algorithm. In order to enhance the cases´ reusability and matching flexibility, the entire execution plan is decomposed into fine-grained fragments before storing to the Case Library. When resolve the emerging service composition problem, through reusing existing cases, the execution path is adjusted to downgrade the problem size and reduce the complexity. For the adjusted execution path, the Genetic Algorithm is used to form an execution plan meeting user´s requirement. A large number of experiments verify the validity of our approach.