Energy-efficient networks under coordinated and uncoordinated sleeping approaches

Wired IP networks handle the bulk of today's communication. These networks are built with over-provisioning and redundancy of devices to support critical activities. However, the activities can vary significantly, resulting in unused network online waste of power. In this study, we examine two existing power-saving approaches for wired IP networks: i) uncoordinated sleeping and (ii) coordinated sleeping. The uncoordinated and coordinated sleeping algorithms investigated are respectively Energy Efficient Ethernet (EEE) and Energy-Aware Routing (EAR) for green OSPF. In addition, we investigate the combination of coordinated and uncoordinated sleeping algorithms, EEE and EAR for green OSPF. The energy performance of the two algorithms and their combination is evaluated in two networks of different dimensions under varying traffic loads. The investigation shows that EEE, EAR for green OSPF and the combination significantly reduce the energy consumption of a network. However, the highest peak of energy conservation is achieved when EAR for green OSPF is activated in an EEE network during lower traffic load periods and deactivated during high traffic load periods.