[LINK] RFI: Geolocation based on IP-Address

[Paul Brooks]

David Lochrin wrote:
>    It's interesting that ip2location could have accurately determined my ISP by simply looking up my IP address in the APNIC database but obviously didn't do so.  However DNS lookups are probably not feasible on the scale thay have in mind, so a local database would be the only way to go.
>   
One of these sites I looked at a few weeks ago used the community itself 
to update the tables - if the location reported for your IP address was 
wrong, you could provide an update on your real location at the website, 
and presumably anyone else with a 'similar' IP address (same /24 
possibly) would then be assumed to have the same location until they got 
a closer update.

In that system it had my IP address as located in Terrey Hills - which 
is only a few suburbs away from my real location in St Ives - and a 
closer guess than Belrose where the Optus cable hub is, and which 
appears in the reverse IP lookup - so presumably someone in Terrey Hills 
with an IP address close to mine registered themselves.

>    Does anyone know how routing works in an ADSL environment?  I connect to Telstra's DSLAM in the local exchange using PPPoE, but does my allocated IP address have any geographical significance?  What would happen if an ISP in Brisbane had ADSL customers all over the country - might an IP address be deallocated from a customer in Canberra when s/he switches off and reallocated to someone in Cairns?
>   
In a service using Telstra Wholesale Layer2 ADSL, the IP address is 
allocated by the ISP, not by Telstra. Interconnect is in the capital 
cities, so usually it will be in state-based blocks - a particular 
address might allocated to someone anywhere within ACT, while a 
Brisbane-based IP address might be re-allocated to another service 
anywhere in QLD, but not Canberra.

Paul.