From my understanding of SEO, websites are optimised for the current location of their IP address.

For example if xxx.xxx.xxx.xx resolves to the UK then you are more likely to get higher rankings in the UK then you are in the USA.

However, my query is when you use a CDN you are storing a cached version of your website across multiple servers at strategic locations across the globe to reduce load time in locations that your trying to target.

Now if you use a CDN and geo-locate the website URL then it only resolves back to the USA (where our IP address resolves too) but it doesn't say it resolves to any other countries. As far as I know you can have multiple IP address resolving to one domain (from different countries).

Do CDN's really help to optimise the location of your website or are they soley meant to optimise load time? Is there a better way to optimise for multiple countries with regards to the resolution of the IP address?

Are VPN's as per this post here relevant to this?

Any advice would be helpful.