arXiv:2610.27318v1 Announce Type: new Abstract: IP geolocation supports many Internet services and operations, including but not limited to content delivery, fraud detection, content localization, and regulatory compliance. However, assessing the reliability and accuracy of IP geolocation providers is challenging and only partially explored. In this paper, we present a longitudinal study evaluating the consistency between RIPE Atlas latency measurements and location estimates from four popular geoproviders as a proxy for geolocation quality. Analyzing six months of data we observe mostly stable consistency levels through time, with fluctuations largely related to changes to the mix of targets being measured by RIPE Atlas each day. We also observe that consistency levels can differ greatly between geoproviders, with IPinfo leading DB-IP (the next best) by 5.4 percentage points for IPv4 and 11.5 percentage points for IPv6. Finally, the analysis reveals distinct degradation patterns across providers for different subsets of IP addresses. For example, for IPv4 router addresses, MaxMind consistency is 10.7 percentage points worse than in the general case while IPinfo is only 1.6 percentage points worse; for IPv6, the pattern flips and routers are geolocated more consistently than non-routers by all providers.