Its not feasable to run a server with zones / world / DB connection over the net. There was discussions about this in the past and I do know of 1 attempt and it was so laggy 1 person couldnt get on.

With me running my test server on an AMD 2.4GH with a Gig of ram and a cable connection i could hold aproximetly 12-15 people befor it got realy laggy, that was on 4.4 tho so it may be a little better on 5.0.