Robustness of queuing network formulas

Abstract

Analyuc models of queuing networks have been observed to give good results for systems which do not conform to the assumptions of classical queuing theory This has been explained to some extent by the recently proposed concept of operational analysis However, the use of operational analysis for prediction of system performance revolves a restrictive assumption, that of homogeneous service tnnes (HST), and practical systems often deviate from HST behavior. It is shown that the main system performance measures are surpnsmgly insensitive to violations of the HST assumption. This further explains the robustness of analyacal models for predicting performance of queuing networks Some issues regarding the operational versus stochasuc approaches are resolved, since it is clatmed that the present analysis, which is carried out m the operational framework, cannot be meaningfully carried out m the stochastic framework.