Green Communications: Principles, Concepts and Practice

Chapter 18Energy-Efficient Protocol Design

Giuseppe Anastasi¹, Simone Brienza¹, Giuseppe Lo Re² and Marco Ortolani²

¹Department of Information Engineering, University of Pisa, Pisa, Italy

²DICGIM, University of Palermo, Palermo, Italy

18.1 Introduction

In developed countries, the total energy consumed by the Internet accounts for approximately 2–3% of the overall worldwide energy consumption [1, 2]. Although this percentage is not so high, its absolute value is very remarkable and has followed an increasing trend over the years [3]. More important, it has been estimated that a large fraction of the overall energy consumed by the Internet is wasted due to an inefficient utilization of infrastructure and user equipment [4]. Hence, significant energy savings could be achieved through appropriate power management strategies. This has stimulated the interest and efforts of the research community. So far, most of the research projects and activities have been driven by telcos and Internet Service Providers (ISPs) and, thus, they have been aimed at reducing the energy consumption mainly in the Internet core (i.e., at routers) and at data centers [5]. Less attention has been devoted to reducing the energy consumption of edge devices at user premises (i.e., PCs, printers, IP phones, displays).

This chapter focuses on solutions for optimizing the energy consumption of PCs and other user equipment connected to the Internet. These edge devices account for the major fraction of the overall ...