Reputation: 15091
I was just installing Ubuntu and noticed it was downloading updates from ca.archive.ubuntu.com. How did it know I was in Canada? As far as I'm aware an IP packet carries no information regarding physical (geographcial location) and there is no stipulation in the Ethernet standard saying anything about information regarding location.
So how do things such as geolocation work? For example this website tells you which country your IP address belongs to. Is it just a matter of looking up an IP address in a table? If so where does the data come from, it's not as if people actively signup to have their IP address associated with the building address?
Upvotes: 1
Views: 702
Reputation: 114014
how does IP address geolocation work, does it just lookup the IP from a table?
Yes, that's exactly how it works.
IP geolocation is nothing more complicated than a database lookup. IP addresses are assigned by IANA to regional governing entities who then assign (sell) them to ISPs, governments and corporations (IBM for example has a dedicated block of IP addresses for themselves because they got into the internet game very early on).
Based on this fact we can sort of figure out where an IP address is located. IANA themselves publish the block level allocations on their site: https://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xml which is rendered beautifully in this XKCD comic: http://xkcd.com/195/.
As for the more detailed info like which city that IP address comes from, to get that information requires more data gathering. Some ISPs may tell you their assignment schemes, most dont. So most databases like whatismyipaddress.com painfully build theirs up by surveys (simply asking people where they are or via smartphone apps tapping into GPS), looking up whois databases (which may or may not lie) and careful guessing.
Upvotes: 3
Reputation: 179
Yes, your IP carries a geolocation as well. I'm not sure that's the best way to describe it, as it doesn't really carry the information (I don't think?). This link gives a pretty good idea of the kind of details they can get from your ISP though:
http://whatismyipaddress.com/geolocation-accuracy
Of course all of that revealing information can be partially negated by using a proxy.
Upvotes: 1