Flow level performance approximations for elastic traffic integrated with prioritized stream traffic

Almost all traffic in today's networks can be classified as being either stream or elastic. The support of these two traffic types is possible either with a Differentiated (DiffServ) or Integrated Services (IntServ) architecture. However, both DiffServ and IntServ rely on efficient scheduling mechanisms and traffic control to meet the requirements of these traffic types. In order to meet the strict delay requirements of stream traffic, the choice of priority scheduling is inevitable. The danger with priority scheduling lies in its potential starvation of lower priority traffic classes for example the elastic traffic class. Therefore, it is essential to understand and capture the relation between stream and elastic traffic behaviour, priority scheduling and traffic control. In this paper we focus on developing simple yet effective approximations to capture this relationship. We assess the accuracy of the approximation against simulations and other well-known simple and straightforward techniques for a wide range of parameters. Results show that our proposed technique is a considerable improvement to other approximation methods and at the same time provides useful insight into various network and traffic parameters