Impact of location on the energy footprint of digital media

In order to accurately assess the impact of geographical location on the energy footprint of digital media requires energy usage models of the Internet that take into account the geographic distance between both users and data providers. In this paper, we present the first such model to do this. Given the specific location of a data source and a user, we use traceroute data to estimate the number and type of network devices involved in data transmission. We then calculate the energy required to transmit the data, combined with energy consumption and utilization data compiled from a number of sources including both academic publications and industry datasheets. Significant quantities of online data are now served by Content Delivery Networks (CDNs), which cache multiple copies of content in locations around the world. We find that CDNs whose primary role is to speed up delivery to the end user also reduce the energy footprint of the network.