Power Aware Management of Packet Switches

In this paper, we extend the idea of dynamic power management (DPM) to network packet switches, devices whose increasing speeds and densities are leading to costly and physically cumbersome power dissipation problems. In particular, we take a system-level approach, examining how operations in an input-queued (IQ) switch can be scheduled to balance power consumption on the one hand with average delay on the other. To accomplish this, we formulate a quadratic cost model which accounts for the power / delay tradeoff and then pose the scheduling problem in terms of a dynamic program. Using techniques from the field of linear quadratic regulation (LQR), we then solve for the optimal control in a relaxed system model and use this to create a novel scheduling algorithm: power aware maximum weight matching (PAMWM). Initial simulation results suggest that, under low load conditions, our algorithm results in significant power savings compared to MWM, with little performance degradation.