Impact of Provider Failures on the Traffic at a University Campus

In this paper we characterize the impact of failures in Brazil´s national education and research network on traffic at a client university. In particular, we study the impact of failures on traffic, user, and application behavior. The failures are interesting in that they persist for several hours and impact only international links, so destinations hosted in Brazil remain reachable. Our results show that although failures in international links have negligible impact on the performance of national traffic, users do adapt their behavior to the unavailability of services hosted abroad. For example, entertainment traffic migrates from Facebook to YouTube, which remains reachable during the analyzed failures, and the fraction of interactive traffic gradually decreases during failures, indicating that users may leave the campus early. We also show that asynchronous applications hosted abroad, like Drop box and SMTP, queue up tasks during the failure and cause traffic bursts when the failure is restored.