Redirecting {DNS} for Ads and Profit
Nicholas C. Weaver, Christian Kreibich, Vern Paxson · 2011
Internet Service Providers (ISPs) increasingly try to grow their profit margins by employing “error traffic monetization,” the practice of redirecting customers whose DNS lookups fail to advertisement-oriented Web servers. A small industry of companies provides the associated machinery for ISPs to engage in this monetization, with the companies often participating in operating the service as well. We conduct a technical analysis of DNS error traffic monetization evident in 66,000 Netalyzr sessions, including fingerprinting derived from patterns seen in the resulting ad landing pages. We identify major players in this industry, their ISP affiliations over time, and available user opt-out mechanisms. One monetization vendor, Paxfire, transgresses the error-based model and also reroutes all user search queries to Bing, Yahoo, and (sometimes) Google via proxy servers controlled or provided by Paxfire.