how to determine location based on ip

how do one determine location based on ip? I'm not asking for any prod开发者_如何学编程uct or service, but rather how to go about implementing it technically.

The ip to country is a rather static mapping. What about more specific locations?

geobyte is a good service to locate ip address. If you are thinking about an algorithm to find location based on IP, I think there is none. It is basically a database look up and you will retrieve the location based on the IP address.