In the metro-core transport segment,up to 81% reduction could be obtained thanks to sleep mode or rate adaptation. 10-30% could be saved thanks to power aware network design. More efficient content distribution combined with efficient transport architecture could lead to 70% reduction and more importantly to a reduction of the traffic volume in the network and processed by equipments, thereby reducing the dependency factor on traffic increase,
The numbers provided above and in Fig.4 should be treated as purely indicative ones, as the savings in various parts of the network depend on many factors such as dimensioning of the reference network. Determining if all these solutions can be combined is part of our future work and it is not addressed here. Instead we mention several important issues.