Performance analysis of flow-based label switching: The single IP flow model

A closed-loop queueing model of flow-based label switches, supporting label reservation protocols of different label-setup and release policies, is pr esented. This model can emulate the behavior of TCP under the label switch when the maximum window size has been achieved and the packet loss rate is negligible. The label-setup policy is that the IP controller does not start to set up a label until the accumulated packets of the same how in the swi tch buffer have exceeded a triggering threshold. Meanwhile, the reserved ba ndwidth is released when the how is detected idle and the label-release tim er has expired. This policy can achieve higher channel utilization with min imal label processing overhead in spite of suffering from certain delay pen alty. To avoid unnecessary TCP timeout or large packet delay under such pol icy, we also introduce a label-setup timer. Norton's theorem is applied to obtain approximate solutions of this queueing model. Although the analytica l method is an approximate one, the simulation results show that the accura cy is high and this model can clearly illustrate how the label-setup and th e lable-release timer affect the system performance. Besides, one can obser ve the trade-off between the throughput and the channel utilization.