Registered in one region, used in another
Live data · updated regularly
In a research paper collaboration we developed the tool "WHEREIS", which geolocates every delegated IPv4 and IPv6 prefix and compares the result against the WHOIS registry that delegated it. These are the prefixes whose measured location falls outside their registry's service region, updated regularly.
- Out-of-region prefixes
- 23,428
- 22,133
- IPv4 prefixes
- 1,295
- IPv6 prefixes
- Oct 10, 2026
- Latest snapshot
- AFRINIC1,946 prefixes2.58%out-of-region2.63% IPv4 · 0.45% IPv6
- ARIN13,899 prefixes1.02%out-of-region1.03% IPv4 · 0.63% IPv6
- RIPE NCC6,543 prefixes0.34%out-of-region0.32% IPv4 · 0.60% IPv6
- LACNIC368 prefixes0.16%out-of-region0.15% IPv4 · 0.36% IPv6
- APNIC672 prefixes0.05%out-of-region0.05% IPv4 · 0.28% IPv6
Where those prefixes actually are
Measured destinations for every prefix whose location falls outside its registry's region. Latency-constrained polygons, aggregated per prefix, intersected with country geometry. Covers the 13,005 prefixes pinned to a single country.
- 1
- 2–6
- 7–20
- 21–103
- 104+
- none
Registered region to measured region
Covers the 21,906 out-of-region prefixes that ProbeNet pins to a single RIR region.
Longitudinal changes
How does out-of-region address space use evolve over time?
- All registries23,428
- AFRINIC1,946
- ARIN13,899
- RIPE NCC6,543
- LACNIC368
- APNIC672
Which geolocation databases notice
Share of registry-inconsistent and fully inconsistent prefixes that each provider already places outside the registering region.
- AFRINICIPinfo99%MaxMind62%DB-IP88%
- ARINIPinfo97%MaxMind56%DB-IP83%
- RIPE NCCIPinfo93%MaxMind70%DB-IP69%
- LACNICIPinfo80%MaxMind41%DB-IP54%
- APNICIPinfo83%MaxMind37%DB-IP50%
Check a prefix
Try or .
Methodology
Every figure on this page comes from the same snapshot, measured the same way.
- The measurement
- ProbeNet measures round-trip latency to responsive addresses in each delegated prefix. The minimum latency bounds how far away the prefix can be at the speed of light in fibre. The feasible area, a speed-of-light polygon, is intersected with country geometry and mapped to RIR service regions.
- The comparison
- WHOIS registration data from all five RIRs supplies the delegating registry and the registered organization's country. A prefix is registry inconsistent when registry and organization agree on a region but the measurement places it elsewhere, and fully inconsistent when all three differ.
- The coverage
- The headline counts every prefix measured outside its registry's region. The map only includes the 13,005 prefixes pinned to a single country and the flow chart the 21,906 pinned to a single region. The method is the paper's, with ProbeNet in place of RIPE Atlas, which is why the counts are far larger than the published tables.
Robert Beverly, Amreesh Phokeer, Oliver Gasser. WHEREIS: IP Address Registration Geo-Consistency. IMC '26, October 12–16 2026, Karlsruhe, Germany.