An object-oriented modeling scheme for distributed applications

A modeling approach is introduced for distributed applications. During the last few years computer networks have dominated the world, forcing the development of applications operating in a network environment. Since new technologies, such as WWW, middleware, and co-operative software, have emerged, distributed application functionality has become rather complex and the requirements from the underlying network increased considerably. Distributed applications usually consist of interacting services provided in a multi-level hierarchy. In order to effectively evaluate their performance through simulation, we introduce a multilayer object-oriented modeling scheme that facilitates the in-depth and detailed distributed application description and supports most popular architectural models, such as the client/server model and its variations. Application functionality is described using predefined operations, which can be further decomposed into simpler ones through a multilayer hierarchy resulting in elementary actions that indicate primitive network operations, such as transfer or processing. Important features of the modeling scheme are extendibility and wide applicability. The simulation environment built according to this modeling scheme is also presented along with an example indicating key features and sample results.