Date Added: Mar 2013
The geographical location of Internet IP addresses is important for academic research, commercial and homeland security applications. While commercial databases claim to have a very high level of accuracy, the correctness of their databases is questionable. Academic tools, based on delay measurements, were shown to have a large range of error. The authors present a novel algorithm that crawls the Internet PoP level graph to improve the accuracy of geo-location, combining information from both geo-location databases and delay measurements. They show that the results provided by the algorithm are more accurate than geo-location databases information while avoiding the pitfalls of delay measurements' usage.