Track Server With A Php Variable

Right now the server is tracked via a cookie, is it possible to easily add in tracking via a php variable? (Maybe this already exists, I'm not sure) Then absolute links etc. wouldn't point to the wrong servers.

Example:

Currently:
http://www.ffxiah.com/item.php?id=90 refers to Rusty bucket on the server your cookie points to
http://www.ffxiah.com/item.php?id=90&server=Ragnarok would refer to Rusty bucket on Ragnarok.

Edit: You could of course just use and id to/instead, like &serverid=1 or whatever.

If no server is specified then the default should fill in to the server stored in your cookie. Hopefully that makes sense!

Actually the server is selected by an ID number (if you look at the server drop down list you can see the ID numbers for the server). In your request you could query
http://www.ffxiah.com/item.php?id=90&sid=20
for a Rusty Bucket on Rangnarok or
http://www.ffxiah.com/item.php?id=90&sid=13
for Ifrit and so on

Ah silly me so it was there the whole time, this is just what I was hoping for. Thanks a lot!