I need to be able to redirect all German users who arrive at http://mysite.com to http://mysite.com/de-de/. Does IIS have this sort of IP routing built in, or is it best to use an ASP.net code solution?
As I understand it: to accurately redirect all German IPs you need to create and redirect an IP table for Germany. This is about 1000 IP ranges. ipaddresslocation.org/ip_ranges/get_ranges.php
IIS has a rewrite/redirect module; whether it will do the GeoIP stuff you think you need is a whole other issue. But really, just because someone's using what some GeoIP database thinks might be a german IP address, does that really mean that the user wants their content in German? Of course not. They could be a tourist, or someone who prefers to use English, or the GeoIP database might be dead wrong (gasp! say it ain't so!) You should respect the user's choice of language (made via the
Accept-Language
header) and not make choices for the user based on erroneous data.