Daily unique hits on pages

[eluser]Unknown[/eluser]
First of all, Greetings to community of the best framework around.

My question is as follows:

I am currently building a Real Estate advertisement website and I need to track unique daily visits for every advertisement.

And what concerns me the most is how to properly log the user. I checked the input class -> ip_address, well it works fine, but how do I log separately users who are behind e.g. router?