Component connectors with qos guarantees

Abstract. Connectors have emerged as a powerful concept for composition and coordination of concurrent activities encapsulated as components and services. Compositional coordination models and languages serve as a means to formally specify and implement component and service connectors. They support large-scale distributed applications by allowing construction of complex component connectors out of simpler ones. Modelling, analysis, and ensuring end-to-end Quality of Service (QoS) represent key concerns in such large-scale distributed applications. In this paper we introduce a compositional model of QoS, called Quantitative Constraint Automata, that reflects the underlying architecture of component/service composition represented by the Reo connector circuits. These can support compositional reasoning about component/service connectors, mod-elled as Reo circuits with QoS properties