Mobile Clouds: Exploiting Distributed Resources in Wireless, Mobile and Social Networks

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Green Mobile Clouds: Making Mobile Devices More Energy Efficient

Smartphones are fun for about half an hour…Then the battery dies.

Alex Smith

Green communications has gained a lot of interest lately and the question here is how mobile clouds can help to improve the energy efficiency of mobile devices. In this chapter the energy-saving potential of mobile clouds is demonstrated. A particular scenario is chosen for this purpose, namely a cooperative download case where users retrieve a desired content in a collaborative manner. The effect on download speed is also investigated. Several cooperative strategies for the mobile cloud are studied and their energy–saving performance is compared.

9.1 Introduction

In the last few years green communications has raised considerable interest in the research community. The carbon footprint of the ICT sector has been discussed intensively and a new research area was born called green communications. The main focus of green communications is not really on the reduction of CO2 emissions, but it is more motivated by the huge electricity bills cloud providers and network operators are facing these days. Without going into detail explaining the relationship between CO2 emissions and green communication, we would just like to state that any reduction of energy consumption is always a good idea. The larger the energy saving, the deeper the economic, technical, usability and environmental impacts. From network operators’ and service providers’ ...