gtnoise.net/nano/ We have implemented NANO deployed clients in a controlled environment on Emulab. Using a combination of controlled (Emulab) and wide-area (PlanetLab) experiments to demonstrate NANO's ability to determine the extent and criteria for differentiation, for a range of current and potential ISP policies on both BitTorrent and HTTP traffic. NANO identifies performance degradations that result from network neutrality violation by an Internet service provider (ISP), such as, differential treatment of specific classes of applications, users, or destinations by the ISP. Existing systems for detecting differential treatment are typically specific to an application or to a particular differentiation mechanism. Because ISPs can change differentiation policies and mechanisms, users need a method to detect differentiation, regardless of the applications that might be subject to differentiation and to the mechanisms used to achieve it. Such a scheme would make detection both robust and difficult to evade. To distinguish differentiation from other causes of degradation (e.g., overload, misconfiguration, failure), NANO uses a statistical method to establish causal relationship between an ISP and observed service performance. NANO agents deployed at participating clients across the Internet collect performance data for selected services and report this information to centralized servers, which analyze the measurements to establish causal relationships between an ISP's policy and performance degradations. This work was done with Mukarram bin Tariq was still a graduate student at Georgia Tech.