Energy management in communication networks: a journey through modeling and optimization glasses

The widespread proliferation of Internet and wireless applications has produced a significant increase of ICT energy footprint. As a response, in the last years, significant efforts have been undertaken to include energy-awareness into network management. Several green networking frameworks consisting in carefully managing the network routing and the power state of network devices have been proposed. Even though the approaches differ on the technologies and sleep modes adopted, they all aim at tailoring the active network resources to the varying traffic needs in order to minimize energy consumption. From a modeling standpoint, this has several commonalities with classical network design and routing problems, even if with different objectives and in a dynamic context. While most research has focused on crucial technological aspects of the green networking schemes, there has been little attention so far on the understanding of the modeling similarities and differences of the proposed solutions. This paper fills the gap by surveying the literature on wired networks energy management with optimization modeling glasses. It follows a tutorial approach that guides through the different components of the models with a unified symbolism. A detailed classification of previous work based on the included modeling issues is also proposed.