Date Added: Dec 2011
The geographical location of Internet IP addresses is important for academic research, commercial and homeland security applications. Thus, both commercial and academic databases and tools are available for mapping IP addresses to geographic locations. Evaluating the accuracy of these mapping services is complex since obtaining diverse large scale ground truth is very hard. In this paper, the authors evaluate mapping services using an algorithm that groups IP addresses to PoPs, based on structure and delay. This way they are able to group close to 100,000 IP addresses world wide into groups that are known to share a geo-location with high confidence.