Understanding Open Proxies in the Wild

This paper conducts an extensive measurement study of open proxies to characterize how much these systems are used, what they are used for, and who uses them. We scanned the Internet to track proxy prevalence and monitored public statistics interfaces to gain insight into the machines hosting open proxies. We estimate that 220 TB of traffic flows through open proxies each day, making them one of the largest overlay networks in existence. We find that automatic traffic taking advantage of multiple vantage points to the Internet overwhelms the traffic of individual ‘end users’ on open proxies. We present a characterization of the workload experienced by these systems that can inform the design of future open access systems.