An application-oriented approach for distributed system modeling and simulation

Complexity of applications operating in a network environment has been considerably increased, since numerous architectural models, such as the client/server model and its extensions, have lately emerged. When dealing with distributed applications, network modeling is not so demanding and modeling solutions for widely used network components are already adopted by commercial tools. We introduce a modeling approach for distributed systems, putting the emphasis on distributed applications. This approach enables the analytical description of applications on the basis of predetermined, high-level operations (or actions) which can be customized to conform to specific architectural models. Operations are ultimately expressed in terms of primitive actions. Through this multi-layer decomposition scheme, in-depth analysis of application mechanisms is promoted. The modeling approach is oriented towards performance evaluation through simulation and a simulation tool has been constructed for this purpose. Modeling examples and a case study for a distributed database banking system are also presented.