Keeping the connectivity and saving the energy in the internet

Nowadays a big effort is spent to reduce the Internet energy consumption. Actual Internet topologies have space to power off some links and devices to reduce the energy consumed in off-peak periods still guaranteeing connectivity among terminals. In this work we leverage the algebraic connectivity of the graph modeling an ISP network in order to define the ESACON (Energy Saving based on Algebraic CONnectivity) algorithm. We then consider the network connectivity as a first target performance to be assured. To this aim we identify a metric based on the algebraic connectivity that, on one side, allows to switch off several links with the consequent significant energy saving and, on the other side, still preserves network connectivity and network performance for efficiently supporting the Internet traffic. We find that ESACON achieves better performance with respect to similar topology-aware approaches; moreover ESACON performance are comparable with ones of a complex traffic-aware solution.