Structure and Stability of Internet Top Lists.

Active Internet measurement studies rely on a list of targets to be scanned.While probing the entire IPv4 address space is feasible for scans of limitedcomplexity, more complex scans do not scale to measuring the full Internet.Thus, a sample of the Internet can be used instead, often in form of a "toplist". The most widely used list is the Alexa Global Top1M list. Despite theirprevalence, use of top lists is seldomly questioned. Little is known abouttheir creation, representativity, potential biases, stability, or overlapbetween lists. As a result, potential consequences of applying top lists inresearch are not known. In this study, we aim to open the discussion on toplists by investigating the aptness of frequently used top lists for empiricalInternet scans, including stability, correlation, and potential biases of suchlists.