Analysing time-related properties of service-oriented systems

We present a formal approach for expressing and analysing time-related properties of service-oriented systems. Our aim is to make it possible for analysts to determine, based on models of services developed at early stages of design, what quality-of-service properties can be expected from, or offered by, the providers of those services. Our approach is based on an extension of SRML, a high-level modelling language developed in the Sensoria project for architectural and behavioural specification of dynamically reconfigurable service-oriented systems. The proposed language extension offers primitives that capture several kinds of delays that may occur during service provision. Quantitative analysis is supported by mapping SRML models to PEPA, a Markovian process algebra supported by a range of efficient software tools that can either confirm that required properties are met or provide feedback that can be used to improve the SRML model.