I am setting up an ecommerce site that caters to a worldwide audience. I would imagine that visitors would come from everywhere, and for whatever reasons, some would be connecting through proxy servers.

My site uses a server that is configured to rate limit connections from the same ip address to protect itself from a DOS attack. So, if a proxy server is heavily used by my visitors, then it would appear to be a DOS.

This is problematic in a sense that it is hard to tell whether the users are genuinely browsing my site or if a DOS is taking place. So my question is, should I give preferential treatment to proxy users on my ecommerce site? If yes, how should this be done. If not, why not?