We provide an overview and results of a long–term field study that captured network interface traffic on–device for 30 participating mobile devices. For the involved devices, the majority of applications installed are found to exhibit network activity, resulting in a high traffic variability. Bursts of data are observed for about 20 minute durations, with an overall average volume of 317 kByte in a two–minute time frame, while exhibiting an average inter–arrival of observed bursts of about 18 hours, albeit with high deviations. We discover a significant dominance of the download direction of network traffic, which to a majority is performed on wireless LAN interfaces. We attribute this behavior to the common practice of mobile data offloading. We furthermore find a lack of distinct long–range dependence or self–similarity in the analyzed traffic, across interface types as well as directions. Our findings could impact the ongoing efforts to decrease networking battery impacts on mobile devices, as little correlation between directions and interfaces we observed in this dataset could hinder anticipatory optimizations though predictions of interface activities.
Index Terms—Mobile profiling; Mobile communication; Communication system traffic;