Aggregation in Multiclass Queueing Networks

Hierarchical modeling is an important technique in the performance analysis of real computer systems. A system is described by a series of levels (or layers), with a different model associated with each level. Hierarchical modeling is particularly suited for representing modern computer systems which are often designed in a top—down fashion. In this paper we propose a computational technique which yields the exact solution of product form multiclass . queueing networks by subsystem aggregation. The method defines a new composite server device factor that is used in the product form solution of the aggregated network. This extension allows us to use the standard convolution algorithms for evaluating the performance measures of a multiclass queueing network represented as hierarchical model.