A Sleep Study for ISP Networks: Evaluating Link Sleeping on Real World Data

Turning off under-utilized network links is a promising energy-saving technique. In this paper, we present Hypnos, a link sleeping system targeted at low-utilization wired networks and assess its efficiency using real-world data from two European ISPs. In those two case studies, we find that Hypnos can turn off more than a third of all links without congesting the network. This confirms the promise of link sleeping in low-utilization networks.