A Framework for Simulation Models of Service-Oriented Architectures

Service-Oriented Architectures (SOA) are one of the main paradigms for future software systems. Since these software systems are composed of a large number of different components it is non trivial to assure an adequate Quality of Service (QoS) of the overall system and performance analysis becomes an important issue. To consider performance issues early in the development process, a model based approach becomes necessary which has to be embedded into the development process of SOA to avoid overhead and assure consistency. In particular the specification of the software system should be used as a base for the resulting performance model. However, since common specification techniques for SOA are very high level, many details have to be added to come to an executable simulation model which is often needed for a detailed analysis of performance or dependability. This paper presents an approach which combines an extended version of process chains to describe the SOA components and some quantitative specifications at the higher levels. For the modelling of the detailed architecture and protocols the simulation tool OMNeT++ is used. Both modelling levels are combined resulting in an executable simulation model for the whole architecture.