Using RIR info to determine geographic location...

Steven M. Bellovin smb at
Fri Dec 21 03:17:36 UTC 2007

On Fri, 21 Dec 2007 02:13:17 +0000
Greg Skinner <gds at> wrote:

> Personally, I have trouble accepting some of the claims the
> geotargeting companies have made, such as Quova's 99.9% to the country
> level, and 95% to the US state level.  ( More info at
> ) Perhaps I'm just part of the
> outlying data; using the "three top search engines" I rarely see them
> get the city correct (ie. where *I* am physically located, as opposed
> to where the registration data says the block is located), and have
> seen some glaring errors for the country in some cases.
> Geotargeting has turned into quite a business, and I'm concerned that
> people who rely on these services do not fully understand the risks.
Some folks are relying on it for serious purposes.  Many Internet
gambling sites use it to avoid serving US customers, for example.
Their risk is criminal liability for the executive -- the have a
strong incentive to get reliable data...  Some sports media sites use it
to enforce local area blackouts; though that doesn't need to be
perfect, if it's too imperfect they risk breach of contract and
expensive lawsuits.

For the advertisers, best effort is probably good enough...

		--Steve Bellovin,

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