How does IP address localization work

**Ranchero** · 30-09-2008

Can anyone please tell me how does an IP address location or region is determined? How is it analyzed and what information is collected. Thanks for any comments.

**Zachary** · 30-09-2008

There are different organizations that compile and market this information. It is easy to find out the general geographic information about where a given IP is located (country) by referring to the databases maintained by the regional numbering authorities, such as ARIN, RIPE, APNIC, etc.

If you check the IPWHOIS for a given address, it usually returns the ISP controlling the address space in which that address is contained. If an entire block is allocated to a customer of the ISP, that information may be available as well

**Big Fish** · 30-09-2008

The Ip address resolves to the geo-location of the ISP's datacenter which manages that IP address block. It may be clsoe or far from the user. It may be as far as a diffrent country actually.

Furthermore the geo-location is based on a geo database to which informaiton is supplied by ISP's themselves. It gets updated on a regular basis, but not continually. So any time there are changes in IP blocks, it takes some tiem until that's reflected in all geo databases.

If the ISP decides they are not intrested in providing more specific details, this often means the ISP's head office lcoaiton is the only thing available.

Bottom line: no geo databases are 100% accurate (up to date) at all time; no geo databases are identical either, as they won't be in sync.

So whichever you query you are likely to get some resutls that don't agree.

Some ISP's like AOL always only provide a single location for all their Ip blocks - since their users will get a random IP for every single pageload, so no particular location is associated permanently with any one IP.