Pinpointing Home and Access Network Delays and Losses Using WiFi Neighbors

Home Internet users and Internet access providers need tools to assist them in diagnosing and troubleshooting network performance problems. Today, expert users may rely on simple techniques using round-trip-measurements to local and remote points to locate delays and losses on an end-to-end path. Unfortunately, round-trip measurements do not provide accurate diagnoses in the presence of asymmetric link capacities and performance, which is often the case in residential access. This paper introduces neighbor-assisted network diagnosis an approach for pinpointing the location of delays and losses (among the home, access, and widearea network), leveraging end-host multi-homing capabilities. We propose two instances of neighbor-assisted network diagnosis, NADD to diagnose delays and NALD for losses, that run on an end host connected simultaneously to the home gateway and to a neighbor WiFi access point. Our evaluation shows that NADD and NALD efficiently detect and distinguish uplink and downlink delays and losses with small error. In addition, we learn from a proof-of-concept deployment in five homes in France that our techniques can work “in the wild.”