A context and service-oriented architecture with adaptive quality of service support
Dina Hafez, Sherif G. Aly, Ahmed Sameh · 2011
Abstract In this paper we extend upon an existing software architecture, namely the Context Oriented Architecture to include support for quality of service. The Context Oriented Architecture is a responsive service oriented infrastructure that transparently monitors application context and allows for custom responses designed by service developers and triggered by conditions in the monitored context. We augment the architecture with a QoS-Broker, which supports QoS representation, discovery, matchmaking, monitoring and self-healing based on Web service standards. Service providers can specify various categories of Web services that differ in their QoS support. Clients are able to dynamically state their QoS requirements. To support standardization, QoS requirements and offers are described using the OWL-Q ontology. Our QoS-Broker matches a group of customers with a group of service offers by converting the problem into a constraint satisfaction problem, and solving it using a matchmaking search algorithm. As a proof of concept, the QoS-Broker monitors the invocation process and takes corrective action if a Web service could not meet the QoS level it claims to support. We verified the feasibility and performance of the QoS-Broker with our prototype implementation and performance measurements. In addition, we showed that group serving has less overhead than individual serving and that our matching logic conforms to the wisdom of the crowd.