2 Matching Annotations
  1. Nov 2017
    1. Figure 4: Typical diurnal cycle for traffi c in the Internet. The scale on the vertical axis is the percentage of total users of the service that are on-line at the time indicated on the horizontal axis. (Source: [21])

      I can't see an easy way to link to this graph itself, but this reference should make it easier to get to this image in future

    2. Our energy calculations show that by 2015, wireless cloud will consume up to 43 TWh, compared to only 9.2 TWh in 2012, an increase of 460%. This is an increase in carbon footprint from 6 megatonnes of CO2 in 2012 to up to 30 megatonnes of CO2 in 2015, the equivalent of adding 4.9 million cars to the roads. Up to 90% of this consumption is attributable to wireless access network technologies, data centres account for only 9%.

      Wow, these numbers. More than 90% in transmission? This makes CDNs and other web performance optimisation techniques much more relevant, than I first thought.