Diagnosing Path Inflation of Mobile Client Traffic

As mobile Internet becomes more popular, carriers and content providers must engineer their topologies, routing configurations, and server deployments to maintain good performance for users of mobile devices. Understanding the impact of Internet topology and routing on mobile users requires broad, longitudinal network measurements conducted from mobile devices. In this work, we are the first to use such a view to quantify and understand the causes of geographically circuitous routes from mobile clients using 1.5 years of measurements from devices on 4 US carriers. We identify the key elements that can affect the Internet routes taken by traffic from mobile users (client location, server locations, carrier topology, carrier/content-provider peering). We then develop a methodology to diagnose the specific cause for inflated routes. Although we observe that the evolution of some carrier networks improves performance in some regions, we also observe many clients - even in major metropolitan areas - that continue to take geographically circuitous routes to content providers, due to limitations in the current topologies.