Applying the DiffServ Model on Cut-Through Networks

Understanding the nature of traffic in high-speed communication systems is essential for achieving QoS in these networks. A first step towards this goal is understanding how basic QoS mechanisms work and affects the network predictability before we introduce more complex mechanisms such as admission control. In this paper we analyse the effect of a DiffServ inspired QoS concept applied to virtual cut-through networks. The main findings from our study are that (i) throughput differentiation can be achieved by weighting of virtual lanes (VL) and by classifying VLs as either low or high priority, (ii) the balance between VL weighting and VL load is not crucial when the network is operating below the saturation point, (iii) jitter, however, is large and good jitter characteristics seems unachievable with such a relative scheme.