%0 Journal Article %T Power-Aware Routing and Network Design with Bundled Links: Solutions and Analysis %A Rosario G. Garroppo %A Stefano Giordano %A Gianfranco Nencioni %A Maria Grazia Scutell¨¤ %J Journal of Computer Networks and Communications %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/154953 %X The paper deeply analyzes a novel network-wide power management problem, called Power-Aware Routing and Network Design with Bundled Links (PARND-BL), which is able to take into account both the relationship between the power consumption and the traffic throughput of the nodes and to power off both the chassis and even the single Physical Interface Card (PIC) composing each link. The solutions of the PARND-BL model have been analyzed by taking into account different aspects associated with the actual applicability in real network scenarios: (i) the time for obtaining the solution, (ii) the deployed network topology and the resulting topology provided by the solution, (iii) the power behavior of the network elements, (iv) the traffic load, (v) the QoS requirement, and (vi) the number of paths to route each traffic demand. Among the most interesting and novel results, our analysis shows that the strategy of minimizing the number of powered-on network elements through the traffic consolidation does not always produce power savings, and the solution of this kind of problems, in some cases, can lead to spliting a single traffic demand into a high number of paths. 1. Introduction Energy saving is one of the most important challenges of the twenty-first century for environmental and economical reasons. From an environmental perspective, due to the lack of diffusion and efficiency of renewable energy, the reduction of power consumption is important because the production of energy is directly related to the emission of carbon dioxide ( ), the main reason of global warming. From an economical point of view, the incremental growth of the energy price and of the power demand of emerging countries makes energy saving a key issue to contain the increase of energy cost in various sectors (industrial, commercial, and residential). Furthermore, we are witnessing an explosive growth in the use of Information and Communication Technologies (ICTs) equipment that is rapidly becoming a major consumer of energy. Indeed, according to the SMART 2020 study [1], emissions from ICT are increasing at a rate of 6% per year, and with such a growth rate they could represent 12% of worldwide emissions by 2020. In this scenario, the research community is studying a set of approaches for improving the energy efficiency of the future Internet. Detailed and up-to-date surveys on the different strategies for energy-efficient networking are presented in [2, 3]. These studies are based on the consideration that current networks are widely overprovisioned and network devices are not energy %U http://www.hindawi.com/journals/jcnc/2013/154953/