Geolocation information with asp.net mvc (cross domain security problem)

How can I get a user's geolocation information (City and Country - internet service provider and internet 开发者_如何学JAVAspeed would also be great) based on their IP address?

I've searched and found several tools for doing this but I seem to run into problems using them with asp.net mvc. Many of them relate to using json and the "security risk" involved in cross domain ajax calls. Any ideas to overcome this problem?

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Any of them use JSONP? With JSONP you can grab data from other domains. It would help if you tell us which tools you want to use.