GeoTargeting Websites for Multiple Country Regions While Preserving SEO Value
"How can we redirect users who come to our site, to the site that most closely matches their country of origin?"
Here's the salient points of our initial take:
1) Geo-targeting based on folder - the XXX site is set up with different folders per country/region, and so it's important that Google understands these folders should be targeted per respective country. Google can generally understand this if the languages are different, but it doesn't hurt to use "Google Webmaster Tools" to make sure each folder is appropriately Geotargeted, as described here
2) To avoid any duplicate content issues and preserve SEO value across folders (in the same language, for example between Europe and the US), we should use the ( rel="canonical" ) links in the Header sections of the US pages.
3) To actually redirect users from XXX.com to XXX.com/ru (for example), the only signal that can really be used is IP address - which isn't always accurate due to propagation of DNS entries and content across global networks. But it can be done - for example:
These solutions provide updated IP address to Country Code mappings (and more), and using these will require some script programming (PHP, ASP, CGI).
Here's a couple of articles on example PHP scripting required for using the Maxmind database: