MaxMind - GeoIP Apache API

国名でACLを切ったり出来るApacheのモジュールだそうです。

国別にページを分けたり、閲覧禁止させたり可能とのこと。

mod_geoip looks up the IP address of the client end user. If you need to input the IP address instead of simply using the client IP address, you will need to use another one of our APIs.
For the country database, mod_geoip sets two environment variables, GEOIP_COUNTRY_CODE and GEOIP_COUNTRY_NAME. For other databases, see the README file included with the mod_geoip API.

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