Building a Power-Proportional Software Router

We aim at improving the power efficiency of network routers without compromising their performance. Using server-based software routers as our prototyping vehicle, we investigate the design of a router that consumes power in proportion to the rate of incoming traffic. We start with an empirical study of power consumption in current software routers, decomposing the total power consumption into its component causes. Informed by this analysis, we develop software mechanisms that exploit the underlying hardware’s power management features for more energyefficient packet processing. We incorporate these mechanisms into Click and demonstrate a router that matches the peak performance of the original (unmodified) router while consuming up to half the power at low loads, with negligible impact on the packet forwarding latency.