A self-adversarial approach to delay analysis under arbitrary scheduling

Abstract

Non-FIFO processing of flows by network nodes is a frequent phenomenon. Unfortunately, the state-of-the-art analytical tool for the computation of performance bounds in packet-switched networks, network calculus, cannot deal well with non-FIFO systems. The problem lies in its conventional service curve definitions. Either the definition is too strict to allow for a concatenation and consequent beneficial end-to-end analysis, or it is too loose and results in infinite delay bounds. Hence, in this paper, we propose a new approach to derive tight bounds in tandems of non-FIFO nodes, the so-called self-adversarial approach. The self-adversarial approach is based on a previously proposed method for calculating performance bounds in feedforward networks [30]. By numerical examples we demonstrate the superiority of the self-adversarial approach over existing methods for the analysis of non-FIFO tandems as well as that for low to medium utilizations it even stays close to corresponding FIFO performance bounds. © 2010 Springer-Verlag.