Energy-as-a-Service (EaaS): On the Efficacy of Multimedia Cloud Computing to Save Smartphone Energy

In spite of the dramatic growth in the number of smartphones in recent years, the challenge of limited energy capacity of these devices has not been solved satisfactorily. However, in the era of cloud computing, the limitation on energy capacity can be eased off in an efficient way by offloading heavy tasks to the cloud. It is important for smartphone and cloud computing developers to have insights into the energy cost of smartphone applications before implementing the offloading techniques. In this paper, we evaluate the energy cost of multimedia applications on smartphones that are connected to Multimedia Cloud Computing (MCC). We have conducted an extensive set of experiments to measure the energy costs to investigate whether or not smartphones save energy by using MCC services. In other words, we investigate the feasibility of MCC to provide the Energy-as-a-Service (EaaS). Specifically, we compared the energy costs for uploading and downloading a video file to and from MCC with the energy costs of encoding the same video file on a smartphone. The aforementioned comparison was performed by using HTTP and FTP Internet protocols with 3G and WiFi network interfaces. All the experiments were conducted on an Android based HTC Nexus One smartphone. Our results show that MCC provides the smartphones with many multimedia functionalities and saves smartphone energy from 30% to 70%.