To fulfill this objective, the general approach consists of analyzing the global energy consumption, identifying where savings can be obtained and proposing solutions that can lead to these reductions. Such a study has already performed for the backbone networks Using an analytical model it was shown that to achieve large savings (i.e. more 10 times reduction of the current power consumption), efforts will need to be concentrated on those techniques that i) reduce the traffic volume in the core (especially the traffic switched in the power-consuming IP network layer) and ii) improve the equipment power efficiency (amount of power in watt per provided capacity in bps).