Geo IP collection / Data collection 101 (Re: Using RIR info to determine geographic location...)

Jeroen Massar jeroen at
Mon Dec 24 07:33:18 UTC 2007

[nicely off-ops, pre-X-mas 101]

James Hess wrote:
> On the other hand, it's perhaps the best geolocators can  _try_ to do...

And they really can't care less about that data. What they do is very
simple, and it maybe explains for you why for instance the big G earns
loads of money: by aggregating data and selling it.

When you go to and you buy something, from your IP, you fill
in your full address details. Then your DHCP expires or for some other
reason your IP changes, and another person gets that same IP, they go to
some other site and fill in their address details. Do this trick for a
couple of hundred rounds. Most very likely the same /24 or some other
size will be re-used in the same geolocation, may that be country, US
state (which actually is just country size compared to Europe), city
etc. After a while you will have a lot of people (they can't care less
about your name though) who have said that when they came from IP
a.b.c.d, that their address was X, as such for IP a.b.c.d you had x%
people saying it was city Y and y% saying it was city Z. Presto, your
accuracy for that IP. Even works when people fill in fake data or use
business/home address (that is why they want you to tag it as such, as
it would screw their stats :)

Now combine a couple of thousands merchant site to increase the data you
get, buy/sell it at country/state/city/street level and you have the
best data ever.

That 0.1% of the data that is 'inaccurate' now is the data of proxies
and other multi-city/state/city IP addresses.

Now you know how to earn money by selling something you collected from
simple a site. Now you probably also understand why data from "Social
Sites" is so valuable: all those people fill in all their data, and that
in a structured way, together with a nice link to 'friends' who also do
that, from which you can so statistical stuff about how accurate it is
as most of them live togheter/closeby or talk about it. They don't
really break any 'privacy' with that, they generally can't care less
about who you are, they just care about the statistics, as that is the
data they will sell.

Can't help you any further though if you are still wondering how the two
G man bought their own Boeings ;)


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 187 bytes
Desc: OpenPGP digital signature
URL: <>

More information about the NANOG mailing list