Mark-and-sweep: getting the "inside" scoop on neighborhood networks

Residential Internet connectivity is growing at a phenomenal rate. A number of recent studies have attempted to characterize this connectivity - measuring coverage and performance of last-mile broadband links - from a various vantage points on the Internet, via wireless APs, and even with user cooperation. These studies, however, sacrifice accuracy or require substantial human time. In this work, we present a novel two-pass method to characterize neighborhood networks. We demonstrate that the two pass method dramatically reduces the time spent in active measurement while retaining accuracy. A case study on two neighborhoods in Pittsburgh provide new and accurate insights into broadband connectivity, including throughput, broadband coverage (DSL vs. cable vs. fiber), NAT configurations, DHCP, DNS usage. The results further characterize 802.11 connectivity in the neighborhood.