Power scaling in network devices

The largest part of routers and switches, today deployed in production networks, has very limited energy saving capabilities, and substantially requires the same amount of energy both when working at full speed or when being idle. In order to dynamically adapt such energy requirements to the real device work load, current approaches foster the introduction of low power idle and power scaling primitives in entire devices, internal components and network interfaces. Starting from these considerations, we propose an analysis of the theoretical and technological limitations in adopting such kind of mechanisms. The results achieved show that the power scaling allows a linear trade-off between consumption and network performance, but the time to switch between two power states may cause a non negligible service interruption.