Accuracy and Coverage Analysis of IP Geolocation Databases

Identifying the geographical location of Internet hosts is crucial for researchers, governments, and commercial entities. While public and commercial geolocation services are commonly employed for this task, their accuracy in locating Internet hosts remains questionable. This paper studies the accuracy and coverage of four popular geolocation databases; MaxMind, DBIP, IP2Location, and IPGeolocationIO. We assess the consistency and comprehensiveness of these services by analyzing the entire IPv4 space. Furthermore, we investigate the issue at the prefix level since geolocation databases typically provide location data at that level. Finally, we create a ground truth dataset by employing a DNS-based approach and publicly available vendor locations to evaluate the accuracy of the databases. Our findings indicate that these databases provide comprehensive coverage, whereas their accuracy is far from satisfactory. Therefore, it is essential to use the information obtained from these databases cautiously and verify its accuracy before making any decisions based on it.