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percentage of (Unknown city)

PostPosted: Tue Mar 29, 2005 8:32 am
by anormal
Hello,

I tried your service in my free counter http://www.anormal-tracker.de and used the lookup with about 40 different IPs. The most city that was returned is: (Unknown city).
So can you please give me the percentage of known cities for the IP addresses?

Re: percentage of (Unknown city)

PostPosted: Tue Mar 29, 2005 11:16 am
by bfolkens
anormal wrote:Hello,

I tried your service in my free counter http://www.anormal-tracker.de and used the lookup with about 40 different IPs. The most city that was returned is: (Unknown city).
So can you please give me the percentage of known cities for the IP addresses?


There are currently (Mar 29, 2005) 890375 entries for cities <-> Class C IP addresses.

If you look at the total class C address space, there are 24-3 = 21 usable network ID bits (minus 3 because we need to account for private networks, reserved space, etc). So 2^21 = 2097152 possible network IDs in the class C space.

Given that we have a possible 2097152 IPs to fill with cities, and we're 890375 addresses on our way, that makes us approx. 42% of the way there.

Fortunately, our biggest jumps happen when an ISP helps out generously by providing an entire network block to us. Then our numbers jump up rapidly (we've had several large contributors this year) ... So keep spreading the word!! :)