Power Efficiency in Communication Networks with Power-Proportional Devices

Power efficiency is an important aspect of the design of any commercial network infrastructure. With measurement studies revealing that the utilization of forwarding devices does not exceed 40% most of the time, it becomes natural to design these devices with power-proportionality in mind; i.e., consuming less power when under-utilized, and more power when highly utilized. While power-proportionality by itself offers power savings, it opens the door for potential extra power savings when traffic is carefully routed across the network to achieve the utilization at devices leading to an optimized overall power consumption. Towards this end, we study different power-proportional models that mimic current industry standards, show how flow rates in a network can be orchestrated by networking devices to minimize the overall power consumption, and study the merit of putting devices to sleep. Our conclusions provide important network design and management guidelines for efficient operation of networking infrastructures.